---------------------------------------------------------- RV10-List Digest Archive --- Total Messages Posted Sun 08/23/09: 23 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:10 AM - Re: LOP (Lean of Peak) Injector Tuning (gary) 2. 07:34 AM - Re: LOP (Lean of Peak) Injector Tuning (N777TY) 3. 07:44 AM - Re: LOP (Lean of Peak) Injector Tuning (John Cox) 4. 08:01 AM - Re: Another Flying RV10 for the book (cloudvalley@comcast.net) 5. 08:24 AM - Re: LOP (Lean of Peak) Injector Tuning (Deems Davis) 6. 09:46 AM - Re: LOP (Lean of Peak) Injector Tuning (Bill DeRouchey) 7. 09:55 AM - Garmin G900X Users Group? (Robin Marks) 8. 10:16 AM - Re: LOP (Lean of Peak) Injector Tuning (Tim Olson) 9. 11:54 AM - Re: LOP (Lean of Peak) Injector Tuning (Marcus Cooper) 10. 02:21 PM - Re: LOP (Lean of Peak) Injector Tuning (Roger Standley) 11. 02:40 PM - Glastar flyer/ RV10 builder (David McNeill) 12. 03:14 PM - Re: Garmin G900X Users Group? (gary) 13. 03:50 PM - Re: LOP (Lean of Peak) Injector Tuning (Kelly McMullen) 14. 04:13 PM - Re: LOP (Lean of Peak) Injector Tuning (Kelly McMullen) 15. 04:21 PM - Re: LOP (Lean of Peak) Injector Tuning (Kelly McMullen) 16. 06:09 PM - Re: Garmin G900X Users Group? (Robin Marks) 17. 06:51 PM - Re: LOP (Lean of Peak) Injector Tuning (richard sipp) 18. 06:55 PM - Re: LOP (Lean of Peak) Injector Tuning (Tim Olson) 19. 07:19 PM - Re: LOP (Lean of Peak) Injector Tuning (David McNeill) 20. 07:35 PM - Re: RV-10 trio pitch servo install (ddnebert) 21. 10:38 PM - Re: Glastar flyer/ RV10 builder (Werner Schneider) 22. 10:52 PM - Re: nose fork (Steven DiNieri) 23. 11:11 PM - Re: Glastar flyer/ RV10 builder (John Cox) ________________________________ Message 1 _____________________________________ Time: 05:10:58 AM PST US From: "gary" Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning Is there a danger with running too much over square? Dick mentions 2" but I have been running more than that (2200 and 26")LOP. I have not seen much info on running over square. Gary Specketer -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp Sent: Saturday, August 22, 2009 11:57 PM Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Tim: Great post as usual on your injector balancing experience. I had very nearly the same experience and results with two minor variations; a complete Airflow Performance system vs. your Silver Hawk and we started by installing .026's in all cylinders and then balancing. I ran most of the tests at 10-11 MSL and verified at the results at 7.5. Don R. felt that at the lower power settings of around 50-60% the flow divider begins to be the determining factor and by going to the smaller .026s the flow divider is taken out of the equation. There was an interesting series of pictures and notes regarding burned pistons (don't remember where I saw them) where the author thought the cause was "rapid" mixture leaning used by LOP operators. He felt the rapid rise in EGT was the cause. I disagree. GAMI recommends the "big pull" from rich to LOP and then a finer adujustment to prevent spending more time in the danger zone of peak to 100 rich of peak. Also with a rapid initial mixture leaning I doubt the cylinder or piston temp will increase before it cools from steady LOP operation. Further at <65% I do not think you can do anything to the mixture that would harm or overstress the engine. Regarding long range cruise I was happy to find that my engine seems equally smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel flow with each 100 RPM reduction at full throttle settings and there is very little airspeed loss as the prop is taking bigger bits (sorta like overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific how to double their range by running "over square and lean". Finally, to prevent the prop driving the engine during higher speed descents I keep the RPM at least "2" oversquare below manifold pressure. This is common practice with the big radials and it would seem equally applicable to our engines. Dick Sipp N110DV 175 hours ________________________________ Message 2 _____________________________________ Time: 07:34:34 AM PST US Subject: RV10-List: Re: LOP (Lean of Peak) Injector Tuning From: "N777TY" Dick, I think you're referring to this document: http://www.eci.aero/pdf/93-6-7.pdf (though, no photos in it..) -------- RV-7A N777TY Read this topic online here: http://forums.matronics.com/viewtopic.php?p=259171#259171 ________________________________ Message 3 _____________________________________ Time: 07:44:01 AM PST US Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning From: "John Cox" The challenge is to avoid Detonation and the earlier than planned destruction of the engine. That can be a factor of compression ratio of the cylinder, quality and octane of the AVGAS, carbon and garbage deposits inside the combustion chamber and the ignition event. The lower the RPM, the higher the throttle the greater the risk. Several pilots are running upward of 10.0:1 pistons, choose their avgas supplier wisely, run a well timed ignition system and gently increase the throttle. GAMI has made a business of educating pilots. Others try marginal gas quality, ragged ignitions and throw caution to the wind. Choose wisely. Fly Safe. Check your % of power tables for LOP operations. John -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of gary Sent: Sunday, August 23, 2009 5:08 AM Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning Is there a danger with running too much over square? Dick mentions 2" but I have been running more than that (2200 and 26")LOP. I have not seen much info on running over square. Gary Specketer -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp Sent: Saturday, August 22, 2009 11:57 PM Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Tim: Great post as usual on your injector balancing experience. I had very nearly the same experience and results with two minor variations; a complete Airflow Performance system vs. your Silver Hawk and we started by installing .026's in all cylinders and then balancing. I ran most of the tests at 10-11 MSL and verified at the results at 7.5. Don R. felt that at the lower power settings of around 50-60% the flow divider begins to be the determining factor and by going to the smaller .026s the flow divider is taken out of the equation. There was an interesting series of pictures and notes regarding burned pistons (don't remember where I saw them) where the author thought the cause was "rapid" mixture leaning used by LOP operators. He felt the rapid rise in EGT was the cause. I disagree. GAMI recommends the "big pull" from rich to LOP and then a finer adujustment to prevent spending more time in the danger zone of peak to 100 rich of peak. Also with a rapid initial mixture leaning I doubt the cylinder or piston temp will increase before it cools from steady LOP operation. Further at <65% I do not think you can do anything to the mixture that would harm or overstress the engine. Regarding long range cruise I was happy to find that my engine seems equally smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel flow with each 100 RPM reduction at full throttle settings and there is very little airspeed loss as the prop is taking bigger bits (sorta like overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific how to double their range by running "over square and lean". Finally, to prevent the prop driving the engine during higher speed descents I keep the RPM at least "2" oversquare below manifold pressure. This is common practice with the big radials and it would seem equally applicable to our engines. Dick Sipp N110DV 175 hours ________________________________ Message 4 _____________________________________ Time: 08:01:29 AM PST US From: cloudvalley@comcast.net Subject: Re: RV10-List: Another Flying RV10 for the book Hi Mike! Doesn't time fly? It seems like yesterday that we were building our tail ki t with you at Wally's in Eugene Oregon.=C2- We are so jealous! Congratula tions. Wish things worked out for us to finish our kit, but we STILL have n ot sold our farm. Making money though at the famres' market, and flying our Grumman Tiger when we can- but so much slower than you will be flying! We just hired a new Realtor who raised our price on the farm and told us he WI LL sell it. He made no ambiguities about that. Then maybe we can get a high performance plane... Congratulations again Mike. We can send you a CD of a lot of pictures I jus t found on a blank CD of our experience at Wally's with you! I thought I ha d lost it. Brian and Ruth ----- Original Message ----- From: "Robin Marks" Sent: Friday, August 21, 2009 8:00:20 AM GMT -08:00 US/Canada Pacific Subject: RE: RV10-List: Another Flying RV10 for the book Fantastic news Mike. Way to go on posting your first flight on Vans site. I need to get something up there before the calendar clicks over another year. I wonder how many Vans Aircraft are really flying? Regardless you now have your own flying -10; enjoy and please fly safe! I will see you are OSH in 2010. Robin Do Not Archive -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of AirMike Sent: Thursday, August 20, 2009 10:48 PM Subject: RV10-List: Another Flying RV10 for the book RV-10 Q/B kit #40663 lifted off with Mike Seager at the controls on Thursday August 13th 2009 at Minden, Nevada. AirMike now with 2 hrs. in the beast. http://www.vansaircraft.com/public/flights.htm A sincere thanks to all the great folks on this list without whose help the task would have been much more difficult. Special koddos to Tim Olson, Dave M, Dave Saylor, Matt, Gary, Albert, Deems, William C.,Scott, Kelly M, Jesse, Stein, Bob C., John C., Jae C., and anyone else whom I may have forgotten. For the newbees starting their projects this forum will yield to you a better and safer aircraft and the opportunity to meet (even electronically) a great group of fine folks. Read Matt's rules - be positive, and do not be afraid to ask what you might think is a foolish question. Respect and helpfulness keeps this a great forum. Fly safe - have fun -------- OSH '09 or Bust (busted) be there someday Q/B Kit - end game Read this topic online here: http://forums.matronics.com/viewtopic.php?p=258937#258937 =========== =========== MS - =========== e - =C2- =C2- =C2- =C2- =C2--Matt Dralle, List Admin. =========== ________________________________ Message 5 _____________________________________ Time: 08:24:47 AM PST US From: Deems Davis Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning All of the LOP information is GREAT. Keep it coming !!!!!!! I have a question: When leaning the engine, the 'old traditional / prior to gages' way was to lean it until it begins to 'stumble' and then richen it up a bit. When I lean using the EGT gages I notice the 'stumble' when the 1st cylinder goes lean. If you continue to lean until all of the remaining cylinders peak (LOP), What happens to the 'stumble' ??? Does it even out / go way with the engine running smooth? Does it persist? Since any changes in the engines smooth running are a concern in flight, I'd appreciate learning what those of you that are routinely running LOP are experiencing. Deems Davis N519PJ http://deemsrv10.com/index.html gary wrote: > > Is there a danger with running too much over square? Dick mentions 2" but I > have been running more than that (2200 and 26")LOP. I have not seen much > info on running over square. > > Gary Specketer > > -----Original Message----- > From: owner-rv10-list-server@matronics.com > [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp > Sent: Saturday, August 22, 2009 11:57 PM > To: rv10-list@matronics.com > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > Tim: > > Great post as usual on your injector balancing experience. I had very > nearly the same experience and results with two minor variations; a complete > > Airflow Performance system vs. your Silver Hawk and we started by installing > > .026's in all cylinders and then balancing. I ran most of the tests at > 10-11 MSL and verified at the results at 7.5. Don R. felt that at the lower > > power settings of around 50-60% the flow divider begins to be the > determining factor and by going to the smaller .026s the flow divider is > taken out of the equation. > > There was an interesting series of pictures and notes regarding burned > pistons (don't remember where I saw them) where the author thought the cause > > was "rapid" mixture leaning used by LOP operators. He felt the rapid rise > in EGT was the cause. I disagree. GAMI recommends the "big pull" from rich > > to LOP and then a finer adujustment to prevent spending more time in the > danger zone of peak to 100 rich of peak. Also with a rapid initial mixture > leaning I doubt the cylinder or piston temp will increase before it cools > from steady LOP operation. Further at <65% I do not think you can do > anything to the mixture that would harm or overstress the engine. > > Regarding long range cruise I was happy to find that my engine seems equally > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel flow > with each 100 RPM reduction at full throttle settings and there is very > little airspeed loss as the prop is taking bigger bits (sorta like > overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific how > > to double their range by running "over square and lean". Finally, to > prevent the prop driving the engine during higher speed descents I keep the > RPM at least "2" oversquare below manifold pressure. This is common > practice with the big radials and it would seem equally applicable to our > engines. > > Dick Sipp > N110DV 175 hours > > > ________________________________ Message 6 _____________________________________ Time: 09:46:24 AM PST US From: Bill DeRouchey Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning I believe tuning the injector nozzles will create a smoother running engine and that in itself has value. However, I have been mystified during these conversations as to the value of running LOP vs fuel economy. There was nev er enough data in the emails to get the whole picture. The-question I alw ays had was-how much speed are you willing to loose to gain how much-fu el efficiency? - Thanks to Dave's pic of his panel and my own experience I was able to put a picture together. - The following numbers are in statute miles and the Density Altitude is simi lar. If we assume that the top speed of our RV-10's is 205mph then Dave is flying 20% (164.5smph) under max and achieving 18.6smpg while leaned to app rox 25deg LOP. An averaged flight in my plane is 6% under max speed (193smp h) achieving 19.1smpg while leaned to peak. My definition of peak is when 3 cylinders drop. - Typical panel setup for me is: WOT, 10-13K feet, 2380-2420rpm, 10.1-10.3gph , lean to peak. - These are only two-datapoints. What are others achieving? And please prov ide the whole picture - what is-the percent under max speed you are willi ng to fly and the miles per gallon you are achieving as a benefit. I assume the whole LOP (other than a smooth engine) is to achieve fuel efficiency. - What am I missing? - Bill DeRouchey N939SB - - - - --- On Sun, 8/23/09, Deems Davis wrote: From: Deems Davis Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning All of the LOP information is GREAT. Keep it coming !!!!!!! I have a questi on: When leaning the engine, the 'old traditional / prior to gages' way was to lean it until it begins to 'stumble' and then richen it up a bit. When I le an using the EGT gages I notice the 'stumble' when the 1st cylinder goes le an. If you continue to lean until all of the remaining cylinders peak (LOP) , What happens to the 'stumble' ??? Does it even out / go way with the engi ne running smooth? Does it persist? Since any changes in the engines smooth running are a concern in flight, I'd appreciate learning what those of you that are routinely running LOP are experiencing. Deems Davis N519PJ http://deemsrv10.com/index.html gary wrote: > > Is there a danger with running too much over square?- Dick mentions 2" but I > have been running more than that (2200 and 26")LOP. I have not seen much > info on running over square. > > Gary Specketer > > -----Original Message----- > From: owner-rv10-list-server@matronics.com > [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp > Sent: Saturday, August 22, 2009 11:57 PM > To: rv10-list@matronics.com > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > Tim: > > Great post as usual on your injector balancing experience.- I had very nearly the same experience and results with two minor variations; a complet e > > Airflow Performance system vs. your Silver Hawk and we started by install ing > > .026's in all cylinders and then balancing.- I ran most of the tests at 10-11 MSL and verified at the results at 7.5.- Don R. felt that at the l ower > > power settings of around 50-60% the flow divider begins to be the determi ning factor and by going to the smaller .026s the flow divider is taken out of the equation. > > There was an interesting series of pictures and notes regarding burned pi stons (don't remember where I saw them) where the author thought the cause > > was "rapid" mixture leaning used by LOP operators.- He felt the rapid r ise in EGT was the cause.- I disagree.- GAMI recommends the "big pull" from rich > > to LOP and then a finer adujustment to prevent spending more time in the danger zone of peak to 100 rich of peak.- Also with a rapid initial mixtu re leaning I doubt the cylinder or piston temp will increase before it cool s from steady LOP operation.- Further at <65% I do not think you can do a nything to the mixture that would harm or overstress the engine. > > Regarding long range cruise I was happy to find that my engine seems equa lly > > smooth at 2250 as at higher RPM.- I see about a 1GPH reduction in fuel flow with each 100 RPM reduction at full throttle settings and there is ver y little airspeed loss as the prop is taking bigger bits (sorta like overdr ive). Charles Lindberg showed the P-38 pilots in the South Pacific how > > to double their range by running "over square and lean".- Finally, to p revent the prop driving the engine during higher speed descents I keep the RPM at least "2" oversquare below manifold pressure.- This is common prac tice with the big radials and it would seem equally applicable to our engin es. > > Dick Sipp > N110DV 175 hours > > > > > > > > > > >--- le, List Admin. ________________________________ Message 7 _____________________________________ Time: 09:55:23 AM PST US Subject: RV10-List: Garmin G900X Users Group? From: "Robin Marks" Does anyone know of a Garmin Users Group? Ideally a G900X or G1000 users group? I have many (basic) questions about my avionics that don't seem to be covered by the 500+ page manual. Robin ________________________________ Message 8 _____________________________________ Time: 10:16:53 AM PST US From: Tim Olson Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning This is just a guess, for me, to answer your question, but first I'll pass on what my experience has been... When I lean up to and past peak, there is never a period where it stumbles. It keeps running smoothly and as you get further and further LOP, you can hear the engine start to lose power... it gets quieter. If you run that way for a couple minutes and adapt to the sound, you will easily hear and feel the extra power come back as you richen it up towards that -25 to -50F LOP again...and feel even more power as you richen it back to ROP operation. The old "lean to stumble" works well with the carbureted planes I guess. (In my opinion though if it's really that non-precise, carbureted engines in general are kind of "sloppy", and not really going to be nearly as good for LOP) Probably everyone should be using a 6 probe monitor for their operations. So my opinion on the answer to the question would be...since you're running a fuel injected engine, if it's stumbling when it gets to peak on one cylinder, I would guess (just a guess) that it won't go away as you keep leaning further. It would probably be the case that something is preventing you from getting it smooth...be it timing, compression, or something else. The hope is that you can determine what exactly that is, and then make it work so it is smooth. This is the big headache for me in the later part of that writeup. My pal with the 10:1 pistons, we really have to apply ourselves to figure that one out. He ordered the .026 injectors, so we'll see soon how that plays out. Maybe that would be all it would take for you too. I'm hoping that we can make it perfect and then provide more info to all others who face the same hurdle. I am just finally able to get to replying today, and I've gotten a couple of great offline emails. One of them brought up something that I should mention that is important and I'll add this warning into the write-up soon. I wrote there that you should use a timing light to time both systems. This is something basically being said by Klaus at Lightspeed. Of course, it's in his interest to urge you to be very precise in determining timing. It would be ideal if you knew it exactly. But, timing a system with a timing light, being up by the prop when it's moving, is a very dangerous thing. The writer, and A&P himself, said that static timing of a mag can be very good. I agree. I felt like a slacker that I've never used a timing light on my plane, but I feel my mag was timed pretty well by standard simple static timing. But, in this extreme case of this 10:1 engine, I'm not sure what to do. Klaus says use a timing light and get it exact...then tweak the systems or maybe just the mag, and do some testing...try advancing a little. I don't know what to say but...BE CAREFUL if you're working near a moving prop....take it from Stein. :) Also, I assumed that with higher compression you would need to slightly retard the timing. That may not be the case. Klaus said LOP sometimes works better with advanced timing. Anyway, he said not to use the adjustable timing knob addition on the lightspeed..it's too dangerous to mess with. But, the one big thing he did say that makes perfect sense is to READ THE INSTALLATION MANUAL AND FOLLOW THE DIRECTIONS. So, we're also going back into the Lightspeed install and going to make sure the engine is set up properly per that manual. Wish it was simple answers for everyone, but there are going to be some unique cases, with the various engine setups. Tim Olson - RV-10 N104CD Deems Davis wrote: > > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a > question: > > When leaning the engine, the 'old traditional / prior to gages' way was > to lean it until it begins to 'stumble' and then richen it up a bit. > When I lean using the EGT gages I notice the 'stumble' when the 1st > cylinder goes lean. If you continue to lean until all of the remaining > cylinders peak (LOP), What happens to the 'stumble' ??? Does it even out > / go way with the engine running smooth? Does it persist? Since any > changes in the engines smooth running are a concern in flight, I'd > appreciate learning what those of you that are routinely running LOP are > experiencing. > > Deems Davis N519PJ > http://deemsrv10.com/index.html > > gary wrote: >> >> Is there a danger with running too much over square? Dick mentions 2" >> but I >> have been running more than that (2200 and 26")LOP. I have not seen much >> info on running over square. >> >> Gary Specketer >> >> -----Original Message----- >> From: owner-rv10-list-server@matronics.com >> [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp >> Sent: Saturday, August 22, 2009 11:57 PM >> To: rv10-list@matronics.com >> Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning >> >> >> Tim: >> >> Great post as usual on your injector balancing experience. I had very >> nearly the same experience and results with two minor variations; a >> complete >> >> Airflow Performance system vs. your Silver Hawk and we started by >> installing >> >> .026's in all cylinders and then balancing. I ran most of the tests >> at 10-11 MSL and verified at the results at 7.5. Don R. felt that at >> the lower >> >> power settings of around 50-60% the flow divider begins to be the >> determining factor and by going to the smaller .026s the flow divider >> is taken out of the equation. >> >> There was an interesting series of pictures and notes regarding burned >> pistons (don't remember where I saw them) where the author thought the >> cause >> >> was "rapid" mixture leaning used by LOP operators. He felt the rapid >> rise in EGT was the cause. I disagree. GAMI recommends the "big >> pull" from rich >> >> to LOP and then a finer adujustment to prevent spending more time in >> the danger zone of peak to 100 rich of peak. Also with a rapid >> initial mixture leaning I doubt the cylinder or piston temp will >> increase before it cools from steady LOP operation. Further at <65% I >> do not think you can do anything to the mixture that would harm or >> overstress the engine. >> >> Regarding long range cruise I was happy to find that my engine seems >> equally >> >> smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel >> flow with each 100 RPM reduction at full throttle settings and there >> is very little airspeed loss as the prop is taking bigger bits (sorta >> like overdrive). Charles Lindberg showed the P-38 pilots in the South >> Pacific how >> >> to double their range by running "over square and lean". Finally, to >> prevent the prop driving the engine during higher speed descents I >> keep the RPM at least "2" oversquare below manifold pressure. This is >> common practice with the big radials and it would seem equally >> applicable to our engines. >> >> Dick Sipp >> N110DV 175 hours >> >> >> >> >> >> >> >> >> >> >> > > > > > ________________________________ Message 9 _____________________________________ Time: 11:54:13 AM PST US From: "Marcus Cooper" Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning Bill, You address an interesting question. The primary debate has been on whether to choose the old school Rich of Peak (ROP) or Lean of Peak (LOP) which is why the big fuel savings over slight airspeed drop numbers. Seems that most of us were taught to either richen slightly after the engine stumbles in the absence of good gauges, or run around 50 to 100 ROP depending on cruise or power requirements. Your choice to go at peak certainly accomplishes most of the LOP intent of saving gas without the speed drop. I have read on the forum somewhere that some companies actually recommend running at peak, whereas I've also read some concerns over that setting so I'm hopefully there are some educated answers out there. My overall understanding is the key is to keep the CHTs under control and otherwise where you set the mixture shouldn't do any damage provided you are under 65% power. Amazing how what should be a fairly straightforward topic has so many perceptions. I for one have been very please with LOP and really appreciate Tim's write-up as I would like to make it even better. I have the same setup and stayed clear of tweaking because I didn't know we had the same injector options as the Airflow Performance setup, so THANKS. Marcus Do not archive From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Bill DeRouchey Sent: Sunday, August 23, 2009 12:38 PM Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning I believe tuning the injector nozzles will create a smoother running engine and that in itself has value. However, I have been mystified during these conversations as to the value of running LOP vs fuel economy. There was never enough data in the emails to get the whole picture. The question I always had was how much speed are you willing to loose to gain how much fuel efficiency? Thanks to Dave's pic of his panel and my own experience I was able to put a picture together. The following numbers are in statute miles and the Density Altitude is similar. If we assume that the top speed of our RV-10's is 205mph then Dave is flying 20% (164.5smph) under max and achieving 18.6smpg while leaned to approx 25deg LOP. An averaged flight in my plane is 6% under max speed (193smph) achieving 19.1smpg while leaned to peak. My definition of peak is when 3 cylinders drop. Typical panel setup for me is: WOT, 10-13K feet, 2380-2420rpm, 10.1-10.3gph, lean to peak. These are only two datapoints. What are others achieving? And please provide the whole picture - what is the percent under max speed you are willing to fly and the miles per gallon you are achieving as a benefit. I assume the whole LOP (other than a smooth engine) is to achieve fuel efficiency. What am I missing? Bill DeRouchey N939SB --- On Sun, 8/23/09, Deems Davis wrote: From: Deems Davis Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a question: When leaning the engine, the 'old traditional / prior to gages' way was to lean it until it begins to 'stumble' and then richen it up a bit. When I lean using the EGT gages I notice the 'stumble' when the 1st cylinder goes lean. If you continue to lean until all of the remaining cylinders peak (LOP), What happens to the 'stumble' ??? Does it even out / go way with the engine running smooth? Does it persist? Since any changes in the engines smooth running are a concern in flight, I'd appreciate learning what those of you that are routinely running LOP are experiencing. Deems Davis N519PJ http://deemsrv10.com/index.html gary wrote: > > > Is there a danger with running too much over square? Dick mentions 2" but I > have been running more than that (2200 and 26")LOP. I have not seen much > info on running over square. > > Gary Specketer > > -----Original Message----- > From: owner-rv10-list-server@matronics.com > [mailto:owner-rv10-list-server@matronics.com ] On Behalf Of richard sipp > Sent: Saturday, August 22, 2009 11:57 PM > To: rv10-list@matronics.com > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > > Tim: > > Great post as usual on your injector balancing experience. I had very nearly the same experience and results with two minor variations; a complete > > Airflow Performance system vs. your Silver Hawk and we started by installing > > .026's in all cylinders and then balancing. I ran most of the tests at 10-11 MSL and verified at the results at 7.5. Don R. felt that at the lower > > power settings of around 50-60% the flow divider begins to be the determining factor and by going to the smaller .026s the flow divider is taken out of the equation. > > There was an interesting series of pictures and notes regarding burned pistons (don't remember where I saw them) where the author thought the cause > > was "rapid" mixture leaning used by LOP operators. He felt the rapid rise in EGT was the cause. I disagree. GAMI recommends the "big pull" from rich > > to LOP and then a finer adujustment to prevent spending more time in the danger zone of peak to 100 rich of peak. Also with a rapid initial mixture leaning I doubt the cylinder or piston temp will increase before it cools from steady LOP operation. Further at <65% I do not think you can do anything to the mixture that would harm or overstress the engine. > > Regarding long range cruise I was happy to find that my engine seems equally > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel flow with each 100 RPM reduction at full throttle settings and there is very little airspeed loss as the prop is taking bigger bits (sorta like overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific how > > to double their range by running "over square and lean". Finally, to prevent the prop driving the engine during higher speed descents I keep the RPM at least "2" oversquare below manifold pressure. This is common practice with the big radials and it would seem equally applicable to our engines. > > Dick Sipp > N110DV 175 hours > > > > > > > > > > ========================http://www.mat==================== ________________________________ Message 10 ____________________________________ Time: 02:21:42 PM PST US From: "Roger Standley" Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Yes, I find this subject interesting, too. I have a question: What are you seeing for peak EGT at various power settings, say at 75%, 65% and 55% power settings? Roger ----- Original Message ----- From: Marcus Cooper To: rv10-list@matronics.com Sent: Sunday, August 23, 2009 11:53 AM Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning Bill, You address an interesting question. The primary debate has been on whether to choose the old school Rich of Peak (ROP) or Lean of Peak (LOP) which is why the big fuel savings over slight airspeed drop numbers. Seems that most of us were taught to either richen slightly after the engine stumbles in the absence of good gauges, or run around 50 to 100 ROP depending on cruise or power requirements. Your choice to go at peak certainly accomplishes most of the LOP intent of saving gas without the speed drop. I have read on the forum somewhere that some companies actually recommend running at peak, whereas I've also read some concerns over that setting so I'm hopefully there are some educated answers out there. My overall understanding is the key is to keep the CHTs under control and otherwise where you set the mixture shouldn't do any damage provided you are under 65% power. Amazing how what should be a fairly straightforward topic has so many perceptions. I for one have been very please with LOP and really appreciate Tim's write-up as I would like to make it even better. I have the same setup and stayed clear of tweaking because I didn't know we had the same injector options as the Airflow Performance setup, so THANKS. Marcus Do not archive From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Bill DeRouchey Sent: Sunday, August 23, 2009 12:38 PM To: rv10-list@matronics.com Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning I believe tuning the injector nozzles will create a smoother running engine and that in itself has value. However, I have been mystified during these conversations as to the value of running LOP vs fuel economy. There was never enough data in the emails to get the whole picture. The question I always had was how much speed are you willing to loose to gain how much fuel efficiency? Thanks to Dave's pic of his panel and my own experience I was able to put a picture together. The following numbers are in statute miles and the Density Altitude is similar. If we assume that the top speed of our RV-10's is 205mph then Dave is flying 20% (164.5smph) under max and achieving 18.6smpg while leaned to approx 25deg LOP. An averaged flight in my plane is 6% under max speed (193smph) achieving 19.1smpg while leaned to peak. My definition of peak is when 3 cylinders drop. Typical panel setup for me is: WOT, 10-13K feet, 2380-2420rpm, 10.1-10.3gph, lean to peak. These are only two datapoints. What are others achieving? And please provide the whole picture - what is the percent under max speed you are willing to fly and the miles per gallon you are achieving as a benefit. I assume the whole LOP (other than a smooth engine) is to achieve fuel efficiency. What am I missing? Bill DeRouchey N939SB --- On Sun, 8/23/09, Deems Davis wrote: From: Deems Davis Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning To: rv10-list@matronics.com Date: Sunday, August 23, 2009, 8:22 AM > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a question: When leaning the engine, the 'old traditional / prior to gages' way was to lean it until it begins to 'stumble' and then richen it up a bit. When I lean using the EGT gages I notice the 'stumble' when the 1st cylinder goes lean. If you continue to lean until all of the remaining cylinders peak (LOP), What happens to the 'stumble' ??? Does it even out / go way with the engine running smooth? Does it persist? Since any changes in the engines smooth running are a concern in flight, I'd appreciate learning what those of you that are routinely running LOP are experiencing. Deems Davis N519PJ http://deemsrv10.com/index.html gary wrote: > > > Is there a danger with running too much over square? Dick mentions 2" but I > have been running more than that (2200 and 26")LOP. I have not seen much > info on running over square. > > Gary Specketer > > -----Original Message----- > From: owner-rv10-list-server@matronics.com > [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp > Sent: Saturday, August 22, 2009 11:57 PM > To: rv10-list@matronics.com > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > > Tim: > > Great post as usual on your injector balancing experience. I had very nearly the same experience and results with two minor variations; a complete > > Airflow Performance system vs. your Silver Hawk and we started by installing > > .026's in all cylinders and then balancing. I ran most of the tests at 10-11 MSL and verified at the results at 7.5. Don R. felt that at the lower > > power settings of around 50-60% the flow divider begins to be the determining factor and by going to the smaller .026s the flow divider is taken out of the equation. > > There was an interesting series of pictures and notes regarding burned pistons (don't remember where I saw them) where the author thought the cause > > was "rapid" mixture leaning used by LOP operators. He felt the rapid rise in EGT was the cause. I disagree. GAMI recommends the "big pull" from rich > > to LOP and then a finer adujustment to prevent spending more time in the danger zone of peak to 100 rich of peak. Also with a rapid initial mixture leaning I doubt the cylinder or piston temp will increase before it cools from steady LOP operation. Further at <65% I do not think you can do anything to the mixture that would harm or overstress the engine. > > Regarding long range cruise I was happy to find that my engine seems equally > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel flow with each 100 RPM reduction at full throttle settings and there is very little airspeed loss as the prop is taking bigger bits (sorta like overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific how > > to double their range by running "over square and lean". Finally, to prevent the prop driving the engine during higher speed descents I keep the RPM at least "2" oversquare below manifold pressure. This is common practice with the big radials and it would seem equally applicable to our engines. > > Dick Sipp > N110DV 175 hours > > > > > > > > > > ========================h ttp://www.mat==================== http://www.matronics.com/Navigator?RV10-Listhttp://forums.matronics.comht tp://www.matronics.com/contribution http://www.matronics.com/Navigator?RV10-List http://www.matronics.com/contribution ________________________________ Message 11 ____________________________________ Time: 02:40:37 PM PST US From: "David McNeill" Subject: RV10-List: Glastar flyer/ RV10 builder IIRC there was an RV10 builder who was flying a Glastar for fun while building. If he will identify himself off list I will send pictures of the use of an RV10 nose fork on the Glastar to improve rough/soft field performance. Just completed the Glastar mod this morning to 15/600-5 main wheels and a 500-5 nose wheel. N46007 RV10 190TT N48007 Glastar 515TT ________________________________ Message 12 ____________________________________ Time: 03:14:58 PM PST US From: "gary" Subject: RE: RV10-List: Garmin G900X Users Group? Robin, if you want to start one, count me in. Gary Specketer _____ From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Robin Marks Sent: Sunday, August 23, 2009 11:55 AM Subject: RV10-List: Garmin G900X Users Group? Does anyone know of a Garmin Users Group? Ideally a G900X or G1000 users group? I have many (basic) questions about my avionics that don't seem to be covered by the 500+ page manual. Robin ________________________________ Message 13 ____________________________________ Time: 03:50:38 PM PST US Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning From: Kelly McMullen Peak depends on a lot of factors besides power setting...OAT, altitude, exact probe placement, type of instrument, etc. I've seen anywhere from 1400 to 1500 peak on the IO-360 in my Mooney. I have UBG16 with fast acting probes mounted 1.5" below exhaust port flange. I try to climb at 1200-1250F EGT, but don't obsess on it. On Sun, Aug 23, 2009 at 2:19 PM, Roger Standley wrote: > Yes, I find this subject interesting, too. > > I have a question: What are you seeing for peak EGT at various power > settings, say at 75%, 65% and 55% power settings? > > Roger > > ----- Original Message ----- > From: Marcus Cooper > To: rv10-list@matronics.com > Sent: Sunday, August 23, 2009 11:53 AM > Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning > > Bill, > > You address an interesting question. The primary debate has been on > whether to choose the old school Rich of Peak (ROP) or Lean of Peak (LOP) > which is why the big fuel savings over slight airspeed drop numbers. Seems > that most of us were taught to either richen slightly after the engine > stumbles in the absence of good gauges, or run around 50 to 100 ROP > depending on cruise or power requirements. Your choice to go at peak > certainly accomplishes most of the LOP intent of saving gas without the > speed drop. > > > I have read on the forum somewhere that some companies actually recommend > running at peak, whereas I've also read some concerns over that setting so > I'm hopefully there are some educated answers out there. My overall > understanding is the key is to keep the CHTs under control and otherwise > where you set the mixture shouldn't do any damage provided you are under 65% > power. Amazing how what should be a fairly straightforward topic has so > many perceptions. > > > I for one have been very please with LOP and really appreciate Tim's > write-up as I would like to make it even better. I have the same setup and > stayed clear of tweaking because I didn't know we had the same injector > options as the Airflow Performance setup, so THANKS. > > > Marcus > > Do not archive > > > From: owner-rv10-list-server@matronics.com > [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Bill DeRouchey > Sent: Sunday, August 23, 2009 12:38 PM > To: rv10-list@matronics.com > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > I believe tuning the injector nozzles will create a smoother running engine > and that in itself has value. However, I have been mystified during these > conversations as to the value of running LOP vs fuel economy. There was > never enough data in the emails to get the whole picture. Thequestion I > always had washow much speed are you willing to loose to gain how muchfuel > efficiency? > > > Thanks to Dave's pic of his panel and my own experience I was able to put a > picture together. > > > The following numbers are in statute miles and the Density Altitude is > similar. If we assume that the top speed of our RV-10's is 205mph then Dave > is flying 20% (164.5smph) under max and achieving 18.6smpg while leaned to > approx 25deg LOP. An averaged flight in my plane is 6% under max speed > (193smph) achieving 19.1smpg while leaned to peak. My definition of peak is > when 3 cylinders drop. > > > Typical panel setup for me is: WOT, 10-13K feet, 2380-2420rpm, 10.1-10.3gph, > lean to peak. > > > These are only twodatapoints. What are others achieving? And please provide > the whole picture - what isthe percent under max speed you are willing to > fly and the miles per gallon you are achieving as a benefit. I assume the > whole LOP (other than a smooth engine) is to achieve fuel efficiency. > > > What am I missing? > > > Bill DeRouchey > > N939SB > > > --- On Sun, 8/23/09, Deems Davis wrote: > > From: Deems Davis > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > To: rv10-list@matronics.com > Date: Sunday, August 23, 2009, 8:22 AM > > > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a > question: > > When leaning the engine, the 'old traditional / prior to gages' way was to > lean it until it begins to 'stumble' and then richen it up a bit. When I > lean using the EGT gages I notice the 'stumble' when the 1st cylinder goes > lean. If you continue to lean until all of the remaining cylinders peak > (LOP), What happens to the 'stumble' ??? Does it even out / go way with the > engine running smooth? Does it persist? Since any changes in the engines > smooth running are a concern in flight, I'd appreciate learning what those > of you that are routinely running LOP are experiencing. > > Deems Davis N519PJ > http://deemsrv10.com/index.html > > gary wrote: >> >> Is there a danger with running too much over square? Dick mentions 2" but >> I >> have been running more than that (2200 and 26")LOP. I have not seen much >> info on running over square. >> >> Gary Specketer >> >> -----Original Message----- >> From: owner-rv10-list-server@matronics.com >> [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp >> Sent: Saturday, August 22, 2009 11:57 PM >> To: rv10-list@matronics.com >> Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning >> >> >> Tim: >> >> Great post as usual on your injector balancing experience. I had very >> nearly the same experience and results with two minor variations; a complete >> >> Airflow Performance system vs. your Silver Hawk and we started by >> installing >> >> .026's in all cylinders and then balancing. I ran most of the tests at >> 10-11 MSL and verified at the results at 7.5. Don R. felt that at the lower >> >> power settings of around 50-60% the flow divider begins to be the >> determining factor and by going to the smaller .026s the flow divider is >> taken out of the equation. >> >> There was an interesting series of pictures and notes regarding burned >> pistons (don't remember where I saw them) where the author thought the cause >> >> was "rapid" mixture leaning used by LOP operators. He felt the rapid rise >> in EGT was the cause. I disagree. GAMI recommends the "big pull" from rich >> >> to LOP and then a finer adujustment to prevent spending more time in the >> danger zone of peak to 100 rich of peak. Also with a rapid initial mixture >> leaning I doubt the cylinder or piston temp will increase before it cools >> from steady LOP operation. Further at <65% I do not think you can do >> anything to the mixture that would harm or overstress the engine. >> >> Regarding long range cruise I was happy to find that my engine seems >> equally >> >> smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel >> flow with each 100 RPM reduction at full throttle settings and there is very >> little airspeed loss as the prop is taking bigger bits (sorta like >> overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific how >> >> to double their range by running "over square and lean". Finally, to >> prevent the prop driving the engine during higher speed descents I keep the >> RPM at least "2" oversquare below manifold pressure. This is common >> practice with the big radials and it would seem equally applicable to our >> engines. >> >> Dick Sipp >> N110DV 175 hours >> >> >> >> >> >> >> >> >> >> ========================http://www.mat==================== > > > http://www.matronics.com/Navigator?RV10-List > > http://forums.matronics.com > > http://www.matronics.com/contribution > > > href="http://www.matronics.com/Navigator?RV10-List">http://www.matronics.com/Navigator?RV10-List > href="http://forums.matronics.com">http://forums.matronics.com > href="http://www.matronics.com/contribution">http://www.matronics.com/c > > ________________________________ Message 14 ____________________________________ Time: 04:13:56 PM PST US From: Kelly McMullen Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Deems, if you get a stumble when first cylinder reaches peak you may need some injector matching. While I may sense a hint of roughness as I get near the last cylinder to peak, there is no stumble and continue to run fine until it wants to quit near 70 LOP. Deems Davis wrote: > > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a > question: > > When leaning the engine, the 'old traditional / prior to gages' way was > to lean it until it begins to 'stumble' and then richen it up a bit. > When I lean using the EGT gages I notice the 'stumble' when the 1st > cylinder goes lean. If you continue to lean until all of the remaining > cylinders peak (LOP), What happens to the 'stumble' ??? Does it even out > / go way with the engine running smooth? Does it persist? Since any > changes in the engines smooth running are a concern in flight, I'd > appreciate learning what those of you that are routinely running LOP are > experiencing. > > Deems Davis N519PJ > http://deemsrv10.com/index.html > ________________________________ Message 15 ____________________________________ Time: 04:21:47 PM PST US From: Kelly McMullen Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Hi Bill, LOP fuel economy is only one part of the picture, and is NOT the main reason to do it. Your engine will run cleaner, use less oil and last longer running LOP. It causes the flame to burn slower(like higher octane) giving a flatter pressure pulse to the piston, so that the peak pressure is less, but the average work is close to same. If you are below 7500(approx) you can add throttle to make up for lost power. As long as you are LOP, power =14.9 * gal/hr. So 10gph=149hp. (57%) 75% then = 13.1 gph, if, and only if, you are running LOP. So if you can find an altitude where you can go LOP and then adjust throttle for 13.1 gph, you should see somewhere around 190mph. Of course once you are high enough that you are at WOT and less than 13.1 your power is less and speed will be less. I typically give up 5-7kts to fly LOP, which is okay as long as I am not fighting a headwind. Bill DeRouchey wrote: > These are only two datapoints. What are others achieving? And please > provide the whole picture - what is the percent under max speed you are > willing to fly and the miles per gallon you are achieving as a benefit. > I assume the whole LOP (other than a smooth engine) is to achieve fuel > efficiency. > > What am I missing? > > Bill DeRouchey > N939SB > > > > > > --- On *Sun, 8/23/09, Deems Davis //* wrote: > > > From: Deems Davis > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > To: rv10-list@matronics.com > Date: Sunday, August 23, 2009, 8:22 AM > > > > > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a > question: > > When leaning the engine, the 'old traditional / prior to gages' way > was to lean it until it begins to 'stumble' and then richen it up a > bit. When I lean using the EGT gages I notice the 'stumble' when the > 1st cylinder goes lean. If you continue to lean until all of the > remaining cylinders peak (LOP), What happens to the 'stumble' ??? > Does it even out / go way with the engine running smooth? Does it > persist? Since any changes in the engines smooth running are a > concern in flight, I'd appreciate learning what those of you that > are routinely running LOP are experiencing. > > Deems Davis N519PJ > http://deemsrv10.com/index.html > > gary wrote: > > > > > > Is there a danger with running too much over square? Dick > mentions 2" but I > > have been running more than that (2200 and 26")LOP. I have not > seen much > > info on running over square. > > > > Gary Specketer > > > > -----Original Message----- > > From: owner-rv10-list-server@matronics.com > > > [mailto:owner-rv10-list-server@matronics.com > ] > On Behalf Of richard sipp > > Sent: Saturday, August 22, 2009 11:57 PM > > To: rv10-list@matronics.com > > > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > > > > > > Tim: > > > > Great post as usual on your injector balancing experience. I had > very nearly the same experience and results with two minor > variations; a complete > > > > Airflow Performance system vs. your Silver Hawk and we started by > installing > > > > .026's in all cylinders and then balancing. I ran most of the > tests at 10-11 MSL and verified at the results at 7.5. Don R. felt > that at the lower > > > > power settings of around 50-60% the flow divider begins to be the > determining factor and by going to the smaller .026s the flow > divider is taken out of the equation. > > > > There was an interesting series of pictures and notes regarding > burned pistons (don't remember where I saw them) where the author > thought the cause > > > > was "rapid" mixture leaning used by LOP operators. He felt the > rapid rise in EGT was the cause. I disagree. GAMI recommends the > "big pull" from rich > > > > to LOP and then a finer adujustment to prevent spending more time > in the danger zone of peak to 100 rich of peak. Also with a rapid > initial mixture leaning I doubt the cylinder or piston temp will > increase before it cools from steady LOP operation. Further at <65% > I do not think you can do anything to the mixture that would harm or > overstress the engine. > > > > Regarding long range cruise I was happy to find that my engine > seems equally > > > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in > fuel flow with each 100 RPM reduction at full throttle settings and > there is very little airspeed loss as the prop is taking bigger bits > (sorta like overdrive). Charles Lindberg showed the P-38 pilots in > the South Pacific how > > > > to double their range by running "over square and lean". > Finally, to prevent the prop driving the engine during higher speed > descents I keep the RPM at least "2" oversquare below manifold > pressure. This is common practice with the big radials and it would > seem equally applicable to our engines. > > > > Dick Sipp > > N110DV 175 hours > > > > > > > > > > > > > > > > > > > > ======================= > http://www.mat==================== > > > > > > * > > > * ________________________________ Message 16 ____________________________________ Time: 06:09:10 PM PST US Subject: RE: RV10-List: Garmin G900X Users Group? From: "Robin Marks" The blind leading the blind? Gary are you flying behind a G900X now? If so maybe we could talk offline to find out where each if us is confused (other than Garmin's poor documentation). Note: I believe Garmin specifically limited it's documentation to limit its liability. Robin From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of gary Sent: Sunday, August 23, 2009 3:12 PM Subject: RE: RV10-List: Garmin G900X Users Group? Robin, if you want to start one, count me in. Gary Specketer ________________________________ From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Robin Marks Sent: Sunday, August 23, 2009 11:55 AM Subject: RV10-List: Garmin G900X Users Group? Does anyone know of a Garmin Users Group? Ideally a G900X or G1000 users group? I have many (basic) questions about my avionics that don't seem to be covered by the 500+ page manual. Robin http://www.matronics.com/Navigator?RV10-List http://forums.matronics.com http://www.matronics.com/contribution Checked by AVG - www.avg.com 08/23/09 06:18:00 ________________________________ Message 17 ____________________________________ Time: 06:51:55 PM PST US From: "richard sipp" Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning There are limits to "oversquare" operation on the power charts in the Lycoming operators manual. They vary with all the other engine parameters but the limits are higher than one would probably guess, several inches MP over RPM in hundreds in most cases. These are the hard to read two page charts and the limit is just a line and is easy to miss. My normal cruise is 55-65% power, 10.5-11.5 GPH and 160-165 KTAS. Dick Sipp ----- Original Message ----- From: "gary" Sent: Sunday, August 23, 2009 8:07 AM Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning > > Is there a danger with running too much over square? Dick mentions 2" but > I > have been running more than that (2200 and 26")LOP. I have not seen much > info on running over square. > > Gary Specketer > > -----Original Message----- > From: owner-rv10-list-server@matronics.com > [mailto:owner-rv10-list-server@matronics.com] On Behalf Of richard sipp > Sent: Saturday, August 22, 2009 11:57 PM > To: rv10-list@matronics.com > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > Tim: > > Great post as usual on your injector balancing experience. I had very > nearly the same experience and results with two minor variations; a > complete > > Airflow Performance system vs. your Silver Hawk and we started by > installing > > .026's in all cylinders and then balancing. I ran most of the tests at > 10-11 MSL and verified at the results at 7.5. Don R. felt that at the > lower > > power settings of around 50-60% the flow divider begins to be the > determining factor and by going to the smaller .026s the flow divider is > taken out of the equation. > > There was an interesting series of pictures and notes regarding burned > pistons (don't remember where I saw them) where the author thought the > cause > > was "rapid" mixture leaning used by LOP operators. He felt the rapid rise > in EGT was the cause. I disagree. GAMI recommends the "big pull" from > rich > > to LOP and then a finer adujustment to prevent spending more time in the > danger zone of peak to 100 rich of peak. Also with a rapid initial > mixture > leaning I doubt the cylinder or piston temp will increase before it cools > from steady LOP operation. Further at <65% I do not think you can do > anything to the mixture that would harm or overstress the engine. > > Regarding long range cruise I was happy to find that my engine seems > equally > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in fuel > flow > with each 100 RPM reduction at full throttle settings and there is very > little airspeed loss as the prop is taking bigger bits (sorta like > overdrive). Charles Lindberg showed the P-38 pilots in the South Pacific > how > > to double their range by running "over square and lean". Finally, to > prevent the prop driving the engine during higher speed descents I keep > the > RPM at least "2" oversquare below manifold pressure. This is common > practice with the big radials and it would seem equally applicable to our > engines. > > Dick Sipp > N110DV 175 hours > > > ________________________________ Message 18 ____________________________________ Time: 06:55:27 PM PST US From: Tim Olson Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Bill, Regarding the speeds, I don't know why Dave was only getting 164.5 statute mph, but my LOP cruise is typically way better than that, which is about 143kts, right? If I am way lean of peak, and/or very heavy loaded, I MAY get slowed down to 155-156kts TAS, but on plenty of trips I'm seeing speeds of 164-166kts at LOP cruise. If I fly ROP, I'd say most commonly I'll see 173-175kts, sometimes slower. I've found that between leaning variations, turbulence, altitudes flown, and loadings, that the speed can be all over the map, but I don't know that I've ever really seen constant enroute cruise figures of less than 152kts on my trips. So if I am getting, say 189-190 statue mph on many flights, and I'm generally burning 9.5-10.5 gph at my most commonly flown altitudes, I'm probably pushing right up near that same 19.1 statue mpg on many flights. There are times I'm a bit less, but loadings and the other factors don't always duplicate themselves. I'll tell you what though, there's no way that I'm not getting better efficiency than someone flying ROP. As Kelly pointed out, it's the temps, the cleanness, and all sorts of other things that are benefits too. I'd say that you will usually lose 6-10kts depending on many factors, such as how far you lean past peak. I usually just go for 25 LOP on the last cyl. to peak. Regarding flying ROP or at peak, like you are talking about, I tend to agree that if you're way down in power like at 65%, you're probably not going to hurt anything too bad. But, for those who are running 50-100 ROP, you probably want to do a bit of studying up. I don't have the numbers committed to memory, but there is a window at higher power settings where you really don't want to stay, and I think in order to stay out of it you really have to either fly WAY ROP, or go LOP. Again, don't quote me, but if you venture over 75% power, I'd avoid that range from maybe 125 to 0 ROP. (Can someone verify that? I've got docs but I'm not going to dig them up right this minute) So I'm not saying you're doing anything wrong, at the lower power levels you can get away with anything. But, I think you picked a pretty lowball datapoint from David if you're going to use his 164.5smph. Scott Schmidt and I both just flew together for 3.75 hours running LOP and we blew that speed away by at least 10kts for the whole trip, on something like 9.5 gph. He was lighter loaded than me and burned about 2 gallons less over the entire leg. So the point is, I don't think most people will give up enough speed to worry about it a whole lot. Tim Olson - RV-10 N104CD Bill DeRouchey wrote: > I believe tuning the injector nozzles will create a smoother running > engine and that in itself has value. However, I have been mystified > during these conversations as to the value of running LOP vs fuel > economy. There was never enough data in the emails to get the whole > picture. The question I always had was how much speed are you willing to > loose to gain how much fuel efficiency? > > Thanks to Dave's pic of his panel and my own experience I was able to > put a picture together. > > The following numbers are in statute miles and the Density Altitude is > similar. If we assume that the top speed of our RV-10's is 205mph then > Dave is flying 20% (164.5smph) under max and achieving 18.6smpg while > leaned to approx 25deg LOP. An averaged flight in my plane is 6% under > max speed (193smph) achieving 19.1smpg while leaned to peak. My > definition of peak is when 3 cylinders drop. > > Typical panel setup for me is: WOT, 10-13K feet, 2380-2420rpm, > 10.1-10.3gph, lean to peak. > > These are only two datapoints. What are others achieving? And please > provide the whole picture - what is the percent under max speed you are > willing to fly and the miles per gallon you are achieving as a benefit. > I assume the whole LOP (other than a smooth engine) is to achieve fuel > efficiency. > > What am I missing? > > Bill DeRouchey > N939SB > > > > > > --- On *Sun, 8/23/09, Deems Davis //* wrote: > > > From: Deems Davis > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > To: rv10-list@matronics.com > Date: Sunday, August 23, 2009, 8:22 AM > > > > > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a > question: > > When leaning the engine, the 'old traditional / prior to gages' way > was to lean it until it begins to 'stumble' and then richen it up a > bit. When I lean using the EGT gages I notice the 'stumble' when the > 1st cylinder goes lean. If you continue to lean until all of the > remaining cylinders peak (LOP), What happens to the 'stumble' ??? > Does it even out / go way with the engine running smooth? Does it > persist? Since any changes in the engines smooth running are a > concern in flight, I'd appreciate learning what those of you that > are routinely running LOP are experiencing. > > Deems Davis N519PJ > http://deemsrv10.com/index.html > > gary wrote: > > > > > > Is there a danger with running too much over square? Dick > mentions 2" but I > > have been running more than that (2200 and 26")LOP. I have not > seen much > > info on running over square. > > > > Gary Specketer > > > > -----Original Message----- > > From: owner-rv10-list-server@matronics.com > > > [mailto:owner-rv10-list-server@matronics.com > ] > On Behalf Of richard sipp > > Sent: Saturday, August 22, 2009 11:57 PM > > To: rv10-list@matronics.com > > > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > > > > > > Tim: > > > > Great post as usual on your injector balancing experience. I had > very nearly the same experience and results with two minor > variations; a complete > > > > Airflow Performance system vs. your Silver Hawk and we started by > installing > > > > .026's in all cylinders and then balancing. I ran most of the > tests at 10-11 MSL and verified at the results at 7.5. Don R. felt > that at the lower > > > > power settings of around 50-60% the flow divider begins to be the > determining factor and by going to the smaller .026s the flow > divider is taken out of the equation. > > > > There was an interesting series of pictures and notes regarding > burned pistons (don't remember where I saw them) where the author > thought the cause > > > > was "rapid" mixture leaning used by LOP operators. He felt the > rapid rise in EGT was the cause. I disagree. GAMI recommends the > "big pull" from rich > > > > to LOP and then a finer adujustment to prevent spending more time > in the danger zone of peak to 100 rich of peak. Also with a rapid > initial mixture leaning I doubt the cylinder or piston temp will > increase before it cools from steady LOP operation. Further at <65% > I do not think you can do anything to the mixture that would harm or > overstress the engine. > > > > Regarding long range cruise I was happy to find that my engine > seems equally > > > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in > fuel flow with each 100 RPM reduction at full throttle settings and > there is very little airspeed loss as the prop is taking bigger bits > (sorta like overdrive). Charles Lindberg showed the P-38 pilots in > the South Pacific how > > > > to double their range by running "over square and lean". > Finally, to prevent the prop driving the engine during higher speed > descents I keep the RPM at least "2" oversquare below manifold > pressure. This is common practice with the big radials and it would > seem equally applicable to our engines. > > > > Dick Sipp > > N110DV 175 hours > > > > > > > > > > > > > > > > > > > > ======================= > http://www.mat==================== > > > > > > * > > > * ________________________________ Message 19 ____________________________________ Time: 07:19:36 PM PST US From: "David McNeill" Subject: RE: RV10-List: LOP (Lean of Peak) Injector Tuning I was not using WOT at 10000 MSL. DA was 14000+. I don't know the weight but we had OSH baggage and camping gear. I typically get about 150KTAS at about 8.5-9 gph. IIRC TAS is affected about 2 mph per 100 pounds gross weight change. My numbers were from pictures just after departing OSH which would mean higher gross weight rather than later in the flight. 36 gals burned in the four hour flight to Tulsa after an OSH taxi and number 6 IFR departure off of R09. After having flown for so many years at slower ground speeds 150KTAS GS or better seems enough. Of course if headwinds are involved I may push the power lever forward but avoiding a fuel stop also figures into the calculation. -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Tim Olson Sent: Sunday, August 23, 2009 6:54 PM Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning Bill, Regarding the speeds, I don't know why Dave was only getting 164.5 statute mph, but my LOP cruise is typically way better than that, which is about 143kts, right? If I am way lean of peak, and/or very heavy loaded, I MAY get slowed down to 155-156kts TAS, but on plenty of trips I'm seeing speeds of 164-166kts at LOP cruise. If I fly ROP, I'd say most commonly I'll see 173-175kts, sometimes slower. I've found that between leaning variations, turbulence, altitudes flown, and loadings, that the speed can be all over the map, but I don't know that I've ever really seen constant enroute cruise figures of less than 152kts on my trips. So if I am getting, say 189-190 statue mph on many flights, and I'm generally burning 9.5-10.5 gph at my most commonly flown altitudes, I'm probably pushing right up near that same 19.1 statue mpg on many flights. There are times I'm a bit less, but loadings and the other factors don't always duplicate themselves. I'll tell you what though, there's no way that I'm not getting better efficiency than someone flying ROP. As Kelly pointed out, it's the temps, the cleanness, and all sorts of other things that are benefits too. I'd say that you will usually lose 6-10kts depending on many factors, such as how far you lean past peak. I usually just go for 25 LOP on the last cyl. to peak. Regarding flying ROP or at peak, like you are talking about, I tend to agree that if you're way down in power like at 65%, you're probably not going to hurt anything too bad. But, for those who are running 50-100 ROP, you probably want to do a bit of studying up. I don't have the numbers committed to memory, but there is a window at higher power settings where you really don't want to stay, and I think in order to stay out of it you really have to either fly WAY ROP, or go LOP. Again, don't quote me, but if you venture over 75% power, I'd avoid that range from maybe 125 to 0 ROP. (Can someone verify that? I've got docs but I'm not going to dig them up right this minute) So I'm not saying you're doing anything wrong, at the lower power levels you can get away with anything. But, I think you picked a pretty lowball datapoint from David if you're going to use his 164.5smph. Scott Schmidt and I both just flew together for 3.75 hours running LOP and we blew that speed away by at least 10kts for the whole trip, on something like 9.5 gph. He was lighter loaded than me and burned about 2 gallons less over the entire leg. So the point is, I don't think most people will give up enough speed to worry about it a whole lot. Tim Olson - RV-10 N104CD Bill DeRouchey wrote: > I believe tuning the injector nozzles will create a smoother running > engine and that in itself has value. However, I have been mystified > during these conversations as to the value of running LOP vs fuel > economy. There was never enough data in the emails to get the whole > picture. The question I always had was how much speed are you willing > to loose to gain how much fuel efficiency? > > Thanks to Dave's pic of his panel and my own experience I was able to > put a picture together. > > The following numbers are in statute miles and the Density Altitude is > similar. If we assume that the top speed of our RV-10's is 205mph then > Dave is flying 20% (164.5smph) under max and achieving 18.6smpg while > leaned to approx 25deg LOP. An averaged flight in my plane is 6% under > max speed (193smph) achieving 19.1smpg while leaned to peak. My > definition of peak is when 3 cylinders drop. > > Typical panel setup for me is: WOT, 10-13K feet, 2380-2420rpm, > 10.1-10.3gph, lean to peak. > > These are only two datapoints. What are others achieving? And please > provide the whole picture - what is the percent under max speed you > are willing to fly and the miles per gallon you are achieving as a benefit. > I assume the whole LOP (other than a smooth engine) is to achieve fuel > efficiency. > > What am I missing? > > Bill DeRouchey > N939SB > > > > > > --- On *Sun, 8/23/09, Deems Davis //* wrote: > > > From: Deems Davis > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > To: rv10-list@matronics.com > Date: Sunday, August 23, 2009, 8:22 AM > > > > > All of the LOP information is GREAT. Keep it coming !!!!!!! I have a > question: > > When leaning the engine, the 'old traditional / prior to gages' way > was to lean it until it begins to 'stumble' and then richen it up a > bit. When I lean using the EGT gages I notice the 'stumble' when the > 1st cylinder goes lean. If you continue to lean until all of the > remaining cylinders peak (LOP), What happens to the 'stumble' ??? > Does it even out / go way with the engine running smooth? Does it > persist? Since any changes in the engines smooth running are a > concern in flight, I'd appreciate learning what those of you that > are routinely running LOP are experiencing. > > Deems Davis N519PJ > http://deemsrv10.com/index.html > > gary wrote: > > > > > > Is there a danger with running too much over square? Dick > mentions 2" but I > > have been running more than that (2200 and 26")LOP. I have not > seen much > > info on running over square. > > > > Gary Specketer > > > > -----Original Message----- > > From: owner-rv10-list-server@matronics.com > > > [mailto:owner-rv10-list-server@matronics.com > ] > On Behalf Of richard sipp > > Sent: Saturday, August 22, 2009 11:57 PM > > To: rv10-list@matronics.com > > > Subject: Re: RV10-List: LOP (Lean of Peak) Injector Tuning > > > > > > > > Tim: > > > > Great post as usual on your injector balancing experience. I had > very nearly the same experience and results with two minor > variations; a complete > > > > Airflow Performance system vs. your Silver Hawk and we started by > installing > > > > .026's in all cylinders and then balancing. I ran most of the > tests at 10-11 MSL and verified at the results at 7.5. Don R. felt > that at the lower > > > > power settings of around 50-60% the flow divider begins to be the > determining factor and by going to the smaller .026s the flow > divider is taken out of the equation. > > > > There was an interesting series of pictures and notes regarding > burned pistons (don't remember where I saw them) where the author > thought the cause > > > > was "rapid" mixture leaning used by LOP operators. He felt the > rapid rise in EGT was the cause. I disagree. GAMI recommends the > "big pull" from rich > > > > to LOP and then a finer adujustment to prevent spending more time > in the danger zone of peak to 100 rich of peak. Also with a rapid > initial mixture leaning I doubt the cylinder or piston temp will > increase before it cools from steady LOP operation. Further at <65% > I do not think you can do anything to the mixture that would harm or > overstress the engine. > > > > Regarding long range cruise I was happy to find that my engine > seems equally > > > > smooth at 2250 as at higher RPM. I see about a 1GPH reduction in > fuel flow with each 100 RPM reduction at full throttle settings and > there is very little airspeed loss as the prop is taking bigger bits > (sorta like overdrive). Charles Lindberg showed the P-38 pilots in > the South Pacific how > > > > to double their range by running "over square and lean". > Finally, to prevent the prop driving the engine during higher speed > descents I keep the RPM at least "2" oversquare below manifold > pressure. This is common practice with the big radials and it would > seem equally applicable to our engines. > > > > Dick Sipp > > N110DV 175 hours > > > > > > > > > > > > > > > > > > > > ======================= > > http://www.mat========= > ========== > > > > > > * > > > * ________________________________ Message 20 ____________________________________ Time: 07:35:35 PM PST US Subject: RV10-List: Re: RV-10 trio pitch servo install From: "ddnebert" Trio has a bracket, parts, and instructions for the wing leveler in the RV-10, but no plans or parts yet for the pitch servo. After discussing with a number of builders, the addition of a pitch servo (at such a reasonable price - $750 - controlled by the MGL Odyssey EFIS) was a good design idea. It was also something I could do now. I'll order another servo for roll later. I contacted Trio and an individual who had built and mounted a pitch servo in a -10, and took pictures of it, and built a reinforced tray that is mounted on the aft end of the battery and elevator bellcrank support platform. They suggested I use whatever parts I could from the wing leveler kit and fashion a reinforced tray. So, I fashioned a 6x7 inch tray from the leftover cutout of the baggage door, cut lengths of 3/4-in angle that I bought at the fly market, and mounted them facing upward for clearance. Drilled, deburred and riveted the angle to the sheet. Lined up the holes to connect the tray to the battery platform - three holes for #8 screws. Marked and drilled six holes to suit the hardware supplied with the servo bracket to mount the servo to the tray (bolt, washer, and lock nut). I mounted the servo tray and it is very stiffly in-place. I attached the servo arm to the wheel with screws to allow for motion at the top of the arc, detents fore and aft, center straight up. Likewise, I positioned the elevator bellcrank arm near-neutral (also vertical) then drilled a hole for a #3 bolt through the arm to hold the servo control connection. Looking around the shop, I found a hexagonal 6-1/2" threaded rod that accommodated the rod ends and nuts supplied with the leveler kit (Vans VA 256) which was the perfect length. Tightened up the rod end nuts, and used three washers between the arms and the rod end for clearance, otherwise keeping the arm connection design as pictured for the leveler servo. Bolted the battery platform back to the ribs. Log entry: http://websites.expercraft.com/douglasn/index.php?q=log_entry&log_id=40960 and pictures: http://websites.expercraft.com/douglasn/images/3368053714a91f7a4158b3.jpg http://websites.expercraft.com/douglasn/images/21209592804a91f7a41c679.jpg -------- RV-10 Builder #40546 Tail mostly done, wings complete, middle of SB fuse Read this topic online here: http://forums.matronics.com/viewtopic.php?p=259232#259232 ________________________________ Message 21 ____________________________________ Time: 10:38:09 PM PST US From: Werner Schneider Subject: Re: RV10-List: Glastar flyer/ RV10 builder David, as far as I can remember there are several, why not post it in the Glastar Net Forum or do you have no account there? Werner do not archive David McNeill wrote: > IIRC there was an RV10 builder who was flying a Glastar for fun while > building. If he will identify himself off list I will send pictures of > the use of an RV10 nose fork on the Glastar to improve rough/soft > field performance. Just completed the Glastar mod this morning to > 15/600-5 main wheels and a 500-5 nose wheel. > > N46007 RV10 190TT > N48007 Glastar 515TT > * > > > * ________________________________ Message 22 ____________________________________ Time: 10:52:19 PM PST US From: "Steven DiNieri" Subject: Re: RV10-List: nose fork Dave, I powdercoated mine and it came out nice. it didn't hurt the bushings at all. steve From: David McNeill Sent: Friday, August 21, 2009 1:33 PM Subject: RV10-List: nose fork Has anyone painted/treated the fork as supplied by Vans? ________________________________ Message 23 ____________________________________ Time: 11:11:54 PM PST US Subject: RE: RV10-List: Glastar flyer/ RV10 builder From: John Cox John Jessen, it is time to step forward for flying the Glastar N531CE whil e your RV-10 N212PJ kit #40328 needs the nose wheel improvement. John Cox From: Werner Schneider Sent: Sun 8/23/2009 10:36 PM Subject: Re: RV10-List: Glastar flyer/ RV10 builder David, as far as I can remember there are several, why not post it in the Glastar Net Forum or do you have no account there? Werner do not archive David McNeill wrote: > IIRC there was an RV10 builder who was flying a Glastar for fun while > building. If he will identify himself off list I will send pictures of > the use of an RV10 nose fork on the Glastar to improve rough/soft > field performance. Just completed the Glastar mod this morning to > 15/600-5 main wheels and a 500-5 nose wheel. > > N46007 RV10 190TT > N48007 Glastar 515TT > * > > > * ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv10-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV10-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rv10-list Browse Digests http://www.matronics.com/digest/rv10-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.