---------------------------------------------------------- JabiruEngine-List Digest Archive --- Total Messages Posted Wed 09/09/09: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:14 AM - Re: Here's an idea that DIDN'T work (Lynn Matteson) 2. 09:18 AM - Re: Here's an idea that DIDN'T work (James, Clive R) 3. 09:20 AM - bing carb (David Brown) 4. 01:27 PM - Re: bing carb (Lynn Matteson) 5. 03:41 PM - Re: Here's an idea that DIDN'T work (Peter Harris) 6. 03:41 PM - Re: Here's an idea that DIDN'T work (Peter Harris) 7. 06:56 PM - Re: Here's an idea that DIDN'T work (Lynn Matteson) 8. 09:54 PM - Re: Here's an idea that DIDN'T work (James, Clive R) 9. 11:38 PM - Re: Here's an idea that DIDN'T work (Peter Harris) 10. 11:38 PM - Re: Here's an idea that DIDN'T work (Peter Harris) ________________________________ Message 1 _____________________________________ Time: 06:14:14 AM PST US From: Lynn Matteson Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work Oh, THAT NACA shape...yes, I am familiar with that shape. I never gave it a thought as to using it for exhaust pipes. I thought when you mentioned NACA yesterday, that there was another shape that I wasn't familiar with....and there are plenty, I'm sure....so I Googled NACA and didn't find much on exhausts. I wonder how the "fishmouth" pipes like were used on the P-40 Allison's would work, and why did they shape those like they did? Seems like I recall it was for reduced visibility at night, but maybe not. The Rotec TBI also has a slight offset to the actuation of the slide, but not as bad as the Aerocarb, and there is no jamming that I've been able to detect. Mine is smooth, and it is a push wire throttle control right up to my homemade bellcrank. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:21 AM, Peter Harris wrote: > Lynn, > I have attached a pic of the modified tail pipes. You will be > familiar with > the shape. There is a progressive reduction in pressure as the exhaust > progresses out the pipe. This eliminates the "bark" and should make > for > reduced back pressure. It was one of those ideas you get in the > middle of > the night. (Normally this NACA shape is used as an air inlet) > I found it softened the tone and is comfortable noise level in flight. > I will look into the Rotec but at present I am running fuel > injection with a > Jenvey throttle body. > The Aerocarb suffers from basic design faults because of the offset > leverage > from the cable attachment. At low throttle settings it can jam and the > harder you pull the cable the harder it jams. > > Peter > ________________________________ Message 2 _____________________________________ Time: 09:18:44 AM PST US Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work From: "James, Clive R" Pete, that looks an interesting idea, do you have a picture from a different angle? I have a single down pipe on my 3300 and there's a 2200 at the field, they are both noisy in comparison with the twin pipe engines, if this style of outlet reduces the 'bark' I'll change it on mine. I have my 2200 pipes cut at an angle and that's really quiet, I didn't do it for the noise rather to stop the floor from getting so warm....pipe were very short. Regards, Clive Jabiru SP 2200 Esqual LS 3300 Both pretty standard! -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn Matteson Sent: 09 September 2009 14:13 Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work --> Oh, THAT NACA shape...yes, I am familiar with that shape. I never gave it a thought as to using it for exhaust pipes. I thought when you mentioned NACA yesterday, that there was another shape that I wasn't familiar with....and there are plenty, I'm sure....so I Googled NACA and didn't find much on exhausts. I wonder how the "fishmouth" pipes like were used on the P-40 Allison's would work, and why did they shape those like they did? Seems like I recall it was for reduced visibility at night, but maybe not. The Rotec TBI also has a slight offset to the actuation of the slide, but not as bad as the Aerocarb, and there is no jamming that I've been able to detect. Mine is smooth, and it is a push wire throttle control right up to my homemade bellcrank. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:21 AM, Peter Harris wrote: > Lynn, > I have attached a pic of the modified tail pipes. You will be familiar > with the shape. There is a progressive reduction in pressure as the > exhaust progresses out the pipe. This eliminates the "bark" and should > make for reduced back pressure. It was one of those ideas you get in > the middle of the night. (Normally this NACA shape is used as an air > inlet) I found it softened the tone and is comfortable noise level in > flight. > I will look into the Rotec but at present I am running fuel injection > with a Jenvey throttle body. > The Aerocarb suffers from basic design faults because of the offset > leverage from the cable attachment. At low throttle settings it can > jam and the harder you pull the cable the harder it jams. > > Peter > ________________________________ Message 3 _____________________________________ Time: 09:20:52 AM PST US Subject: JabiruEngine-List: bing carb From: "David Brown" Lynn, Listers I know that all EGT's Are relative and that during my tuning experience that I saw EGT's for short periods that were 1410-1420's. can you give an EGT no. that represents peak. I am wondering how close I am to running at that point that is 50 degrees rich of peak that can be destructive to an engine? David Brown 601XL JAB 3300 N601EX 125 HRS Subject: JabiruEngine-List: Bing Carb From: "David Brown" I bent up a set of X vanes made of Stainless steel thin sheet about 2" long, not made to rotate the air, but to straighten it just before the carbi. Inserted it in the scat tubing. Bent flanges so that it keeps tension on the sides of the tubing so that it cannot move. Max EGTs range from 1330 to 1370 now. No reduction of power, maybe a little increase. I wouldn't trade my bing now. I get about 4.7GPH at 2750 RPM, 115 MPH. Good idea, David....now if you had a way to lean the Bing (maybe a HACman?), you'd really love it. : ) I'm not sure that the HACman works at all altitudes, though....I just don't know much about it. I did a similar thing with a fiberglass tube with X vanes, built right into my Bing air intake, and found that rotating the air intake would affect EGT's and which banks were hotter, left to right. It would be nice to have a cabin-controlled set of X vanes so that instant observation of results could be obtained. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying ________________________________ Message 4 _____________________________________ Time: 01:27:48 PM PST US From: Lynn Matteson Subject: Re: JabiruEngine-List: bing carb Well, for an example....and I don't know how bad this was....I saw 1468 F. today. I was flying along at WOT (3010 rpm), and my #3 got that high. That was as high as it got, and when it leveled off at that temp, I reduced throttle to about 2850, and the EGT's came down. I think this is another example of the fuel slamming forward at high revs, and the rear cylinders going lean. Then when I went into "lean of peak" mode, I was getting 1370-1390's F., and CHT's of 288-305 F. When things settle down after leaning out, my EGT's had a spread of 47-60-something, and CHT's were within 3 F. at one point, and stayed at less than a 15 F. spread. Usually when I'm turning about 2850 rpm and I go into "lean of peak EGT" mode, the #4 gets there first (as I'm leaning) followed by #3, and I usually watch the #3 (for no good reason at all, and this may be wrong) get to about 1430-1440, and then it starts to drop. At the time it peaks....1440 for example...I'll subtract 20 and lean to 1420. At this point there is still power, and it hasn't started to stumble yet. If I pull it much more lean, it will start to sag, and I enrichen j-u-s-t a tad. I almost always see 3.2-3.4 gph on the fuel flow meter at this point. If I cut the revs down to the low 2700's it will flow under 3.0 gph. At about 2580 or so, 2.5-2.8 gph, but I'm not going anywhere, just counting the cows. : ) I've looked at the tops and edges of my pistons (small goose-neck flashlight), and there are no signs of problems yet. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 761.4 hrs Countdown to 1000 hrs~239 Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:17 PM, David Brown wrote: > > > Lynn, Listers > > I know that all EGT's Are relative and that during my tuning > experience > that I saw EGT's for short periods that were 1410-1420's. can you > give > an EGT no. that represents peak. I am wondering how close I am to > running at that point that is 50 degrees rich of peak that can be > destructive to an engine? > > David Brown > 601XL JAB 3300 > N601EX 125 HRS ________________________________ Message 5 _____________________________________ Time: 03:41:41 PM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Clive, I have only the three pics attached but here also is a paper on NACA inlet design. Using a felt pen on the pipes and an angle grinder I just made it look like a NACA inlet. Regards Peter -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of James, Clive R Sent: Thursday, 10 September 2009 1:44 AM Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Pete, that looks an interesting idea, do you have a picture from a different angle? I have a single down pipe on my 3300 and there's a 2200 at the field, they are both noisy in comparison with the twin pipe engines, if this style of outlet reduces the 'bark' I'll change it on mine. I have my 2200 pipes cut at an angle and that's really quiet, I didn't do it for the noise rather to stop the floor from getting so warm....pipe were very short. Regards, Clive Jabiru SP 2200 Esqual LS 3300 Both pretty standard! -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn Matteson Sent: 09 September 2009 14:13 Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work --> Oh, THAT NACA shape...yes, I am familiar with that shape. I never gave it a thought as to using it for exhaust pipes. I thought when you mentioned NACA yesterday, that there was another shape that I wasn't familiar with....and there are plenty, I'm sure....so I Googled NACA and didn't find much on exhausts. I wonder how the "fishmouth" pipes like were used on the P-40 Allison's would work, and why did they shape those like they did? Seems like I recall it was for reduced visibility at night, but maybe not. The Rotec TBI also has a slight offset to the actuation of the slide, but not as bad as the Aerocarb, and there is no jamming that I've been able to detect. Mine is smooth, and it is a push wire throttle control right up to my homemade bellcrank. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:21 AM, Peter Harris wrote: > Lynn, > I have attached a pic of the modified tail pipes. You will be familiar > with the shape. There is a progressive reduction in pressure as the > exhaust progresses out the pipe. This eliminates the "bark" and should > make for reduced back pressure. It was one of those ideas you get in > the middle of the night. (Normally this NACA shape is used as an air > inlet) I found it softened the tone and is comfortable noise level in > flight. > I will look into the Rotec but at present I am running fuel injection > with a Jenvey throttle body. > The Aerocarb suffers from basic design faults because of the offset > leverage from the cable attachment. At low throttle settings it can > jam and the harder you pull the cable the harder it jams. > > Peter > Checked by AVG - www.avg.com 06:48:00 ________________________________ Message 6 _____________________________________ Time: 03:41:43 PM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Lynn have you got a link to details on the Rotec TBI? Thanks Peter -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn Matteson Sent: Wednesday, 9 September 2009 11:13 PM Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work Oh, THAT NACA shape...yes, I am familiar with that shape. I never gave it a thought as to using it for exhaust pipes. I thought when you mentioned NACA yesterday, that there was another shape that I wasn't familiar with....and there are plenty, I'm sure....so I Googled NACA and didn't find much on exhausts. I wonder how the "fishmouth" pipes like were used on the P-40 Allison's would work, and why did they shape those like they did? Seems like I recall it was for reduced visibility at night, but maybe not. The Rotec TBI also has a slight offset to the actuation of the slide, but not as bad as the Aerocarb, and there is no jamming that I've been able to detect. Mine is smooth, and it is a push wire throttle control right up to my homemade bellcrank. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:21 AM, Peter Harris wrote: > Lynn, > I have attached a pic of the modified tail pipes. You will be > familiar with > the shape. There is a progressive reduction in pressure as the exhaust > progresses out the pipe. This eliminates the "bark" and should make > for > reduced back pressure. It was one of those ideas you get in the > middle of > the night. (Normally this NACA shape is used as an air inlet) > I found it softened the tone and is comfortable noise level in flight. > I will look into the Rotec but at present I am running fuel > injection with a > Jenvey throttle body. > The Aerocarb suffers from basic design faults because of the offset > leverage > from the cable attachment. At low throttle settings it can jam and the > harder you pull the cable the harder it jams. > > Peter > Checked by AVG - www.avg.com 06:48:00 ________________________________ Message 7 _____________________________________ Time: 06:56:01 PM PST US From: Lynn Matteson Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work Here ya go, Peter- http://www.rotecradialengines.com/TBI/TBI.htm Are your pipes made of aluminum? They look like it...at least from the collector to the NACA cut. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 761.4 hrs Countdown to 1000 hrs~239 to go Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 6:37 PM, Peter Harris wrote: > > > Lynn have you got a link to details on the Rotec TBI? > Thanks > Peter > ________________________________ Message 8 _____________________________________ Time: 09:54:58 PM PST US Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work From: "James, Clive R" That's great thanks Pete, felt pen and grinder and I'm off to the hangar! If nothing else they look really trendy! Will match the 4 Naca scoops I have on the new cowling. Regards, Clive -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Peter Harris Sent: 09 September 2009 23:29 Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Clive, I have only the three pics attached but here also is a paper on NACA inlet design. Using a felt pen on the pipes and an angle grinder I just made it look like a NACA inlet. Regards Peter -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of James, Clive R Sent: Thursday, 10 September 2009 1:44 AM Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Pete, that looks an interesting idea, do you have a picture from a different angle? I have a single down pipe on my 3300 and there's a 2200 at the field, they are both noisy in comparison with the twin pipe engines, if this style of outlet reduces the 'bark' I'll change it on mine. I have my 2200 pipes cut at an angle and that's really quiet, I didn't do it for the noise rather to stop the floor from getting so warm....pipe were very short. Regards, Clive Jabiru SP 2200 Esqual LS 3300 Both pretty standard! -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn Matteson Sent: 09 September 2009 14:13 Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work --> Oh, THAT NACA shape...yes, I am familiar with that shape. I never gave it a thought as to using it for exhaust pipes. I thought when you mentioned NACA yesterday, that there was another shape that I wasn't familiar with....and there are plenty, I'm sure....so I Googled NACA and didn't find much on exhausts. I wonder how the "fishmouth" pipes like were used on the P-40 Allison's would work, and why did they shape those like they did? Seems like I recall it was for reduced visibility at night, but maybe not. The Rotec TBI also has a slight offset to the actuation of the slide, but not as bad as the Aerocarb, and there is no jamming that I've been able to detect. Mine is smooth, and it is a push wire throttle control right up to my homemade bellcrank. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:21 AM, Peter Harris wrote: > Lynn, > I have attached a pic of the modified tail pipes. You will be familiar > with the shape. There is a progressive reduction in pressure as the > exhaust progresses out the pipe. This eliminates the "bark" and should > make for reduced back pressure. It was one of those ideas you get in > the middle of the night. (Normally this NACA shape is used as an air > inlet) I found it softened the tone and is comfortable noise level in > flight. > I will look into the Rotec but at present I am running fuel injection > with a Jenvey throttle body. > The Aerocarb suffers from basic design faults because of the offset > leverage from the cable attachment. At low throttle settings it can > jam and the harder you pull the cable the harder it jams. > > Peter > Checked by AVG - www.avg.com 06:48:00 ________________________________ Message 9 _____________________________________ Time: 11:38:25 PM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Lynn they are Stainless steel. I see that the Rotec cable attachment is offset but not so bad as the Aerocarb. It looks well made but is expensive. Peter -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn Matteson Sent: Thursday, 10 September 2009 11:55 AM Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work Here ya go, Peter- http://www.rotecradialengines.com/TBI/TBI.htm Are your pipes made of aluminum? They look like it...at least from the collector to the NACA cut. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 761.4 hrs Countdown to 1000 hrs~239 to go Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 6:37 PM, Peter Harris wrote: > > > Lynn have you got a link to details on the Rotec TBI? > Thanks > Peter > Checked by AVG - www.avg.com 17:50:00 ________________________________ Message 10 ____________________________________ Time: 11:38:34 PM PST US From: "Peter Harris" Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work I would like to know how you find the result Clive when you get the time. Peter -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of James, Clive R Sent: Thursday, 10 September 2009 2:45 PM Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work That's great thanks Pete, felt pen and grinder and I'm off to the hangar! If nothing else they look really trendy! Will match the 4 Naca scoops I have on the new cowling. Regards, Clive -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Peter Harris Sent: 09 September 2009 23:29 Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Clive, I have only the three pics attached but here also is a paper on NACA inlet design. Using a felt pen on the pipes and an angle grinder I just made it look like a NACA inlet. Regards Peter -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of James, Clive R Sent: Thursday, 10 September 2009 1:44 AM Subject: RE: JabiruEngine-List: Here's an idea that DIDN'T work Pete, that looks an interesting idea, do you have a picture from a different angle? I have a single down pipe on my 3300 and there's a 2200 at the field, they are both noisy in comparison with the twin pipe engines, if this style of outlet reduces the 'bark' I'll change it on mine. I have my 2200 pipes cut at an angle and that's really quiet, I didn't do it for the noise rather to stop the floor from getting so warm....pipe were very short. Regards, Clive Jabiru SP 2200 Esqual LS 3300 Both pretty standard! -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Lynn Matteson Sent: 09 September 2009 14:13 Subject: Re: JabiruEngine-List: Here's an idea that DIDN'T work --> Oh, THAT NACA shape...yes, I am familiar with that shape. I never gave it a thought as to using it for exhaust pipes. I thought when you mentioned NACA yesterday, that there was another shape that I wasn't familiar with....and there are plenty, I'm sure....so I Googled NACA and didn't find much on exhausts. I wonder how the "fishmouth" pipes like were used on the P-40 Allison's would work, and why did they shape those like they did? Seems like I recall it was for reduced visibility at night, but maybe not. The Rotec TBI also has a slight offset to the actuation of the slide, but not as bad as the Aerocarb, and there is no jamming that I've been able to detect. Mine is smooth, and it is a push wire throttle control right up to my homemade bellcrank. Lynn Matteson Kitfox IV Speedster, taildragger Jabiru 2200, #2062, 760.3 hrs Sensenich 62"x46" Wood prop Electroair direct-fire ignition system Rotec TBI-40 injection Status: flying On Sep 9, 2009, at 12:21 AM, Peter Harris wrote: > Lynn, > I have attached a pic of the modified tail pipes. You will be familiar > with the shape. There is a progressive reduction in pressure as the > exhaust progresses out the pipe. This eliminates the "bark" and should > make for reduced back pressure. It was one of those ideas you get in > the middle of the night. (Normally this NACA shape is used as an air > inlet) I found it softened the tone and is comfortable noise level in > flight. > I will look into the Rotec but at present I am running fuel injection > with a Jenvey throttle body. > The Aerocarb suffers from basic design faults because of the offset > leverage from the cable attachment. At low throttle settings it can > jam and the harder you pull the cable the harder it jams. > > Peter > Checked by AVG - www.avg.com 06:48:00 Checked by AVG - www.avg.com 17:50:00 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message jabiruengine-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/JabiruEngine-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/jabiruengine-list Browse Digests http://www.matronics.com/digest/jabiruengine-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.