Today's Message Index:
----------------------
1. 03:41 AM - Re: CJ6A mixture (Was: MAP and RPM) (Ernie)
2. 03:51 AM - Re: CJ6A mixture (Was: MAP and RPM) (Ernie)
3. 04:36 AM - Operating Restrictions (cpayne@joimail.com)
4. 05:10 AM - Re: CJ6A mixture (Was: MAP and RPM) (Brian Lloyd)
5. 05:24 AM - malevolent weather (Brian Lloyd)
6. 05:33 AM - Re: CJ6A mixture (Was: MAP and RPM) (Brian Lloyd)
7. 09:30 AM - Re: MP RPM (RiteAngle3@aol.com)
8. 09:50 AM - Re: CJ6A mixture (Was: MAP and RPM) (Jon Boede)
9. 10:16 AM - Lean Vs. Rich (was MAP and RPM) (Womens Specialty Care ObGyn)
10. 01:29 PM - Re: Re: MP RPM (FOUGAPILOT@aol.com)
11. 02:52 PM - Re: CJ6A mixture (Was: MAP and RPM) (Ron Davis)
12. 03:27 PM - Re: CJ6A mixture (Was: MAP and RPM) (cjpilot710@aol.com)
13. 03:57 PM - Re: CJ6A mixture (Was: MAP and RPM) sample EDM-700 data IO-520 (Robert Mortara)
14. 05:51 PM - Re: CJ6A mixture (Was: MAP and RPM) (Brian Lloyd)
15. 06:04 PM - Re: CJ6A mixture (Was: MAP and RPM) (Brian Lloyd)
16. 06:12 PM - RU coming? (cjpilot710@aol.com)
17. 11:36 PM - Re: Lean Vs. Rich (was MAP and RPM) (Walt Lannon)
Message 1
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
Because of advertising! I know I can get a $200 EGT guage, but then I read
the ad that only monitoring one cylinder isnt accurate since you need to
know the leanest cylinder. So then I'm forced to buy the $2000 9 cylinder
monitoring system, but then I cant just get the multichannel EGT system
without adding the fuel flow option, so now I'm up to $3000. Well there you
see...........I cant afford a $3000 EGT guage.
Ernie
----- Original Message -----
From: "Brian Lloyd" <brian@lloyd.com>
Subject: Re: Yak-List: CJ6A mixture (Was: MAP and RPM)
> --> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
>
> Ernie wrote:
> > --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
> >
> > So based on your last post running LOP on a carburated flat engine would
not
> > be a good idea.
>
> Right. But the engine will tell you because it will run roughly.
>
> > And concerning my Housai, since I rarely fly higer than 3000
> > ft I never touch the mixture lever.
>
> As I said, most people don't know what is happening with the mixture so
they do what you do and leave a lot fuel behind.
>
> The thing I find difficult to understand is why, after spending $75,000 or
more on an airplane many pilots are unwilling to spend another $200 for an
EGT gauge.
>
> --
>
> Brian Lloyd 6501 Red Hook Plaza, Suite 201
> brian@lloyd.com St. Thomas, VI 00802
> +1.340.998.9447 - voice +1.360.838.9669 - fax
> GMT-4
>
>
Message 2
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
Yep,
I have the mixture/throttle tab still in place, so I can only push the
mixture as far as the throttle. The guy I bought the plane from who is
rather knowledgeable about planes said to leave it alone under 3 grand, the
engine will run cooler and I wont see that much more fuel consumption. Above
3000 MSL he said to just move the mixture control to the throttle stop and I
should be in the ball park. Obviously there used to be a chart on the
throttle mixture quadrant (in chinese) which used to outline where to put
the lever based on altitude, MAP and RPM, but I've never seen that chart, so
I just wing it. I once told this story when I first bought the airplane.
I was cruising along at around 8500 ft, and I was doing as the previous
owner had mention on the way up, which was to just push the mixture lever to
the throttle stop. Well by the time I got to 8500 ft I was at full throttle.
So I figured I'd lean the old fashioned way, move the lever slowly, untill
the engine ran rough, and then just enrichen a little. Well, the engine
never ran rough all the way to the throttle stop, so I figured the last guy
was right, then about 30 seconds after moving the lever to full lean, the
engine just quit. So I immediately pulled the mixture back and she came back
to life. So basically leaning this engine without an EGT guage is a black
art.
Ernie
----- Original Message -----
From: "Robert Mortara" <rob@robinhill.com>
Subject: RE: Yak-List: CJ6A mixture (Was: MAP and RPM)
> --> Yak-List message posted by: "Robert Mortara" <rob@robinhill.com>
>
> Ernie are you serious about never leaning you CJ?
>
> I start leaning about 30 seconds after I start my engine. Full rich on
take
> off and start leaning after about 1 minute when I back down the throttle
> and RPM mixture about 1/2.
>
> In cruse my mixture is almost all the way forward. I find it hard to see
the
> EGT to tell if I am LOP or Peak a digital would be allot better.
>
> rob
>
>
Message 3
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| Subject: | Operating Restrictions |
--> Yak-List message posted by: cpayne@joimail.com
The restrictions I got were all of those that apply to:
Phase II, Group III, "General", and "Applicable ALL" of
8130-2E. Too numerous to recite here.
Craig Payne
Message 4
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
Ernie wrote:
> --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
>
> Because of advertising! I know I can get a $200 EGT gauge, but then I read
> the ad that only monitoring one cylinder isnt accurate since you need to
> know the leanest cylinder. So then I'm forced to buy the $2000 9 cylinder
> monitoring system, but then I cant just get the multichannel EGT system
> without adding the fuel flow option, so now I'm up to $3000. Well there you
> see...........I cant afford a $3000 EGT gauge.
Well, I suspect you are posting this in jest but I am going to treat it as serious.
In a flat engine you have either a carburetor or multipoint continuous-flow fuel
injection. The former is bad about seeing to it that the air and fuel end up
at the same place. Given that the carb just meters fuel and doesn't vaporize
it and mix it with the air, you have two different densities of material going
down the induction system. They don't necessarily end up in the same place.
One cylinder gets more air, another gets more fuel. The result is huge differences
in mixture between the cylinders that vary with throttle setting and
RPM. You need a multichannel EGT to find the leanest cylinder.
With fuel injection things are a little better because the same amount of fuel
is injected right at the intake valve for each cylinder. Each cylinder gets exactly
the same fuel. But not all intake risers flow the same amount of air so
while the fuel distribution is even, air distribution is not. The solution
is to change the sizes of the injector orifices to match the fuel flow to the
air flow. That is what GAMI does with their GAMI-jectors.
We don't have these problems with our radial engines. They have superchargers.
Most people think the supercharger has something to do with increasing the manifold
pressure but its real job is to act like a giant KitchenAid blender to
mix the air and the liquid fuel coming from the carburetor. Those whirling vanes
help atomize and vaporize the fuel. What makes it to the cylinders is a
uniform fuel-air mixture ready to burn. This is why lean-of-peak operation was
normal in the big radial engines of old. They didn't use EGT gauges but they
didn't need them either. Instead they had a torque gauge. They would set the
power, lean until they saw a certain drop in torque (they were now on the lean
side of peak EGT) and then increase MAP until the torque came back up to the
desired value (torque X RPM = HP).
So, is a single-probe EGT useful for setting the mixture in our radial engines?
Most assuredly. Unless something is wrong with the engine, all the cylinders
receive the same fuel-air mixture. You just want to see where the EGT peaks.
You can put the probe anywhere in the exhaust stack you want to.
Of course, JPI doesn't want you to know that because they want you to give them
$3000 for their super-sexy engine monitor. It is a really nice instrument.
It is really useful for troubleshooting things like fouled plugs. Knowing exactly
which plug is fouled is really useful when your other prospect is to pull
18 plugs. If I had so much money I didn't care about $3000 I would buy one.
But for $2800 I can pull a lot of plugs.
--
Brian Lloyd 6501 Red Hook Plaza, Suite 201
brian@lloyd.com St. Thomas, VI 00802
+1.340.998.9447 - voice +1.360.838.9669 - fax
GMT-4
Message 5
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| Subject: | malevolent weather |
--> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
What is it about weather that it knows when you are going flying, eh? I was planning
to get airborne and head for the states in about 45 minutes. A supercell
popped up over SW Puerto Rico heading NE, right into my path. It even has
a SIGMET to go with it. Tops to FL 550. Red stuff all over the RADAR. (It is
actually looking like it might be dissipating now.) 1-800-VFR-NOTRECOMMENDED
says, "VFR Not Recommended." Duh. But as I told the briefer, "like I am going
to go IFR into this stuff? At least VFR I can see it and turn around." He
conceded that was the better choice. We both agreed that sitting on the ground
is an even better choice.
<sigh> For those of you who want to commiserate, see:
http://www.ssd.noaa.gov/PS/TROP/DATA/RT/watl-ir4-loop.html (GOES east IR loop for the Caribbean)
http://www.srh.noaa.gov/radar/loop/DS.p20-r/si.tjua.shtml (long-range RADAR loop for Puerto Rico)
My desired path is 310M for about 470 nm.
Bah, humbug.
--
Brian Lloyd 6501 Red Hook Plaza, Suite 201
brian@lloyd.com St. Thomas, VI 00802
+1.340.998.9447 - voice +1.360.838.9669 - fax
GMT-4
Message 6
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
Ernie wrote:
> I have the mixture/throttle tab still in place, so I can only push the
> mixture as far as the throttle. The guy I bought the plane from who is
> rather knowledgeable about planes said to leave it alone under 3 grand, the
> engine will run cooler and I wont see that much more fuel consumption. Above
> 3000 MSL he said to just move the mixture control to the throttle stop and I
> should be in the ball park. Obviously there used to be a chart on the
> throttle mixture quadrant (in Chinese) which used to outline where to put
> the lever based on altitude, MAP and RPM, but I've never seen that chart, so
> I just wing it. I once told this story when I first bought the airplane.
And those of us who have EGT gauges have discovered that this leaves the engine
running quite rich. On the ground I usually have the mixture almost all the
way lean to keep the engine running smoothly. On climbout I start leaning right
away after I reduce the RPM to 2250. I adjust the mixture to stay at about
150F rich of peak EGT until I pass through about 5000' and then I start leaning
more aggressively. You can feel the difference in the available power from
the engine if you do this.
> I was cruising along at around 8500 ft, and I was doing as the previous
> owner had mention on the way up, which was to just push the mixture lever to
> the throttle stop. Well by the time I got to 8500 ft I was at full throttle.
> So I figured I'd lean the old fashioned way, move the lever slowly, until
> the engine ran rough, and then just enrichen a little. Well, the engine
> never ran rough all the way to the throttle stop,
That is because the mixture is the same in all the cylinders. It never will run
rough. If you get it too lean it will just quit but it will never run rough.
> so I figured the last guy
> was right, then about 30 seconds after moving the lever to full lean, the
> engine just quit. So I immediately pulled the mixture back and she came back
> to life. So basically leaning this engine without an EGT gauge is a black
> art.
No, you keep leaning until the engines doesn't want to run anymore and then enrichen
until it does. Seems you figured it out all by yourself. No worries.
:
)
--
Brian Lloyd 6501 Red Hook Plaza, Suite 201
brian@lloyd.com St. Thomas, VI 00802
+1.340.998.9447 - voice +1.360.838.9669 - fax
GMT-4
Message 7
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--> Yak-List message posted by: RiteAngle3@aol.com
That is flat engines and that is an old wives tale.
Brian,
You are 100% correct!
If we could get rid of all the wives tales aviation would be a lot safer, let
see, it ruined a lot of Malibu engines, Killed the Cessna 175 (which I loved)
and causes a lot of mechanics to still assemble engines not in accordance
with the manufactures recommendations! Back in the '60s when flying the DC-3's
same thing try to keep MP above RPM.
The designers didn't come up with the numbers for someone who had no
experience with them to change!
Elbie Mendenhall
retired, flown most types of engines flat & round from Aeronca, Szekley to P&
W jets (except the M-14, but hope to change that soon)!
Message 8
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: "Jon Boede" <jon@email.net>
Ok, Brian... you talked me into it. What flavor of EGT gauge do you like,
and where precisely did you mount it?
And to think that my wife said there's nothing I wanted for Christmas. :-)
Jon
> --> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
>
> Ernie wrote:
>
>> I have the mixture/throttle tab still in place, so I can only push the
>> mixture as far as the throttle. The guy I bought the plane from who is
>> rather knowledgeable about planes said to leave it alone under 3
>> grand, the engine will run cooler and I wont see that much more fuel
>> consumption. Above 3000 MSL he said to just move the mixture control
>> to the throttle stop and I should be in the ball park. Obviously there
>> used to be a chart on the throttle mixture quadrant (in Chinese) which
>> used to outline where to put the lever based on altitude, MAP and RPM,
>> but I've never seen that chart, so I just wing it. I once told this
>> story when I first bought the airplane.
>
> And those of us who have EGT gauges have discovered that this leaves the
> engine running quite rich. On the ground I usually have the mixture
> almost all the way lean to keep the engine running smoothly. On
> climbout I start leaning right away after I reduce the RPM to 2250. I
> adjust the mixture to stay at about 150F rich of peak EGT until I pass
> through about 5000' and then I start leaning more aggressively. You can
> feel the difference in the available power from the engine if you do
> this.
>
>> I was cruising along at around 8500 ft, and I was doing as the
>> previous owner had mention on the way up, which was to just push the
>> mixture lever to the throttle stop. Well by the time I got to 8500 ft
>> I was at full throttle. So I figured I'd lean the old fashioned way,
>> move the lever slowly, until the engine ran rough, and then just
>> enrichen a little. Well, the engine never ran rough all the way to the
>> throttle stop,
>
> That is because the mixture is the same in all the cylinders. It never
> will run rough. If you get it too lean it will just quit but it will
> never run rough.
>
>> so I figured the last guy
>> was right, then about 30 seconds after moving the lever to full lean,
>> the engine just quit. So I immediately pulled the mixture back and she
>> came back to life. So basically leaning this engine without an EGT
>> gauge is a black art.
>
> No, you keep leaning until the engines doesn't want to run anymore and
> then enrichen until it does. Seems you figured it out all by yourself.
> No worries. : )
>
> --
>
> Brian Lloyd 6501 Red Hook Plaza, Suite 201
> brian@lloyd.com St. Thomas, VI 00802
> +1.340.998.9447 - voice +1.360.838.9669 - fax
> GMT-4
>
>
Message 9
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| Subject: | Lean Vs. Rich (was MAP and RPM) |
--> Yak-List message posted by: "Womens Specialty Care ObGyn" <drc@wscare.com>
Lean of peak EGT vs. Rich of peak EGT
For a very detailed and excellent explanation of the two options see the GAMI injector
site.
But I will try to summarize.
There is an ideal mixture for optimum combustion rate in the cylinder (stochiometrics
for any chemistry buffs)
For T.O. we all operate traditionally at full rich (more gas than air as it relates
to the ideal mixture) then we lean once cruise power is set. as we lean
and get close to the ideal mixture HP increases and so does heat as the mixture
is more efficiently burned. Then the ideal mixture and max power output is
reached as signaled by the peak EGT. If we continue to lean then HP decreases,
fuel flow decreases and temps decrease. The HP and temp falls off faster than
it rises on the "rich " side of the curve.
Because of the steep fall off on the "lean" side of the curve fuel flow becomes
critical and if the fuel flow is not balanced well to all cylinders then the
engine seems to run rough - which we have all experienced. This is the principle
behind making variable size injectors to keep the fuel flow similar in all
cylinders. This is what GAMI's do - particularly for the flat Continental engines
because of the asymmetric fuel distribution system on the top of the engine.
Historically manufactures recommended rich of peak to keep the engine running
smooth and cool. Now with differential injectors we can keep the engines
running smooth and cool on the lean side of peak.
Hope that helps - more details are available with the graphs at the GAMI site.
HerbC
Message 10
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--> Yak-List message posted by: FOUGAPILOT@aol.com
In a message dated 23/10/2003 12:30:48 PM Eastern Daylight Time,
RiteAngle3@aol.com writes:
> (except the M-14, but hope to change that soon)!
>
Keeping the best for last are we.....LOL
Message 11
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
I'm sure you meant to say that horsepower = (torque X RPM) divided by 5252
What is metric horsepower? I've never come across that term. The metric
system properly uses KW for engine power, but they often list horsepower
too. I wasn't aware that there was a "metric horsepower" that was different
from ours (techinically, I think horsepoer was a British invention- but it's
ours now).
----- Original Message -----
From: "Brian Lloyd" <brian@lloyd.com>
Subject: Re: Yak-List: CJ6A mixture (Was: MAP and RPM)
> --> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
>
> Ernie wrote:
>
> > --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
> >
> > Because of advertising! I know I can get a $200 EGT gauge, but then I
read
> > the ad that only monitoring one cylinder isnt accurate since you need to
> > know the leanest cylinder. So then I'm forced to buy the $2000 9
cylinder
> > monitoring system, but then I cant just get the multichannel EGT system
> > without adding the fuel flow option, so now I'm up to $3000. Well there
you
> > see...........I cant afford a $3000 EGT gauge.
>
> Well, I suspect you are posting this in jest but I am going to treat it as
serious.
>
> In a flat engine you have either a carburetor or multipoint
continuous-flow fuel injection. The former is bad about seeing to it that
the air and fuel end up at the same place. Given that the carb just meters
fuel and doesn't vaporize it and mix it with the air, you have two different
densities of material going down the induction system. They don't
necessarily end up in the same place. One cylinder gets more air, another
gets more fuel. The result is huge differences in mixture between the
cylinders that vary with throttle setting and RPM. You need a multichannel
EGT to find the leanest cylinder.
>
> With fuel injection things are a little better because the same amount of
fuel is injected right at the intake valve for each cylinder. Each cylinder
gets exactly the same fuel. But not all intake risers flow the same amount
of air so while the fuel distribution is even, air distribution is not. The
solution is to change the sizes of the injector orifices to match the fuel
flow to the air flow. That is what GAMI does with their GAMI-jectors.
>
> We don't have these problems with our radial engines. They have
superchargers. Most people think the supercharger has something to do with
increasing the manifold pressure but its real job is to act like a giant
KitchenAid blender to mix the air and the liquid fuel coming from the
carburetor. Those whirling vanes help atomize and vaporize the fuel. What
makes it to the cylinders is a uniform fuel-air mixture ready to burn. This
is why lean-of-peak operation was normal in the big radial engines of old.
They didn't use EGT gauges but they didn't need them either. Instead they
had a torque gauge. They would set the power, lean until they saw a certain
drop in torque (they were now on the lean side of peak EGT) and then
increase MAP until the torque came back up to the desired value (torque X
RPM = HP).
>
> So, is a single-probe EGT useful for setting the mixture in our radial
engines? Most assuredly. Unless something is wrong with the engine, all
the cylinders receive the same fuel-air mixture. You just want to see where
the EGT peaks. You can put the probe anywhere in the exhaust stack you want
to.
>
> Of course, JPI doesn't want you to know that because they want you to give
them $3000 for their super-sexy engine monitor. It is a really nice
instrument. It is really useful for troubleshooting things like fouled
plugs. Knowing exactly which plug is fouled is really useful when your
other prospect is to pull 18 plugs. If I had so much money I didn't care
about $3000 I would buy one. But for $2800 I can pull a lot of plugs.
>
> --
>
> Brian Lloyd 6501 Red Hook Plaza, Suite 201
> brian@lloyd.com St. Thomas, VI 00802
> +1.340.998.9447 - voice +1.360.838.9669 - fax
> GMT-4
>
>
Message 12
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: cjpilot710@aol.com
In a message dated 10/23/2003 5:52:46 PM Eastern Daylight Time,
l39parts@hotmail.com writes:
> . I wasn't aware that there was a "metric horsepower" that was different
> from ours (techinically, I think horsepoer was a British invention- but it's
> ours now).
>
>
>
Yep. It had to do something to about how much coal a set number of horses
could lift out of mine.
Jim Goolsby
"They that can give up essential liberty to obtain a little safety,
deserve neither liberty nor safety"
Benjamin Franklin 1759
"With my shield, or on it"
Trojan Warriors BC
"The reason older men are like fine wine. When young, they are like grapes
until some woman stomps all over them."
Unknown older man.
Message 13
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| Subject: | CJ6A mixture (Was: MAP and RPM) sample EDM-700 data IO-520 |
--> Yak-List message posted by: "Robert Mortara" <rob@robinhill.com>
Any one install a edm-700 multi port EGT CHT in their CJ or Yak? If so what
is the engine doing which cyl peaks 1st which cyl runs the hottest is the
EGT spread very far.
I have one in my Bonanza and has saved my Bacon several times including
today ( showed Buss voltage at 11.3 v- a bad battery which would have run
down low enough to turn off the charging system when extending the gear) On
previous occasions it has showed me bad valves ,tripped over voltage relay
( this was over water while listening to music fat dumb and happy) ,clogged
injector and bad baffling. To be able to identify these items before they
became a major issue was well worth the $3000.
The CJ is for fun not long distance travel but I am considering Installing a
engine monitor just so I can see what is happening in the engine.
following is some sample data from my A-36
EZSave 10/23/03
EDM- 700 V 292 J.P.Instruments (C) 1998
Aircraft Number N462Q__
Flight #71 8/25/03 19:24:6
Eng Deg F OAT Deg F F/F GPH
Duration 1.34Hours Interval 6 seconds
E1 E2 E3 E4 E5 E6 C1
C2 C3 C4 C5 C6 OIL DIF CLD
OAT BAT FF USD
19:26:54 1319 1260 1188 1094 1152 1067
267 277 259 257 252 261 109
252 0 77
13.9 2.2 16.6
19:27:00 1295 1254 1194 1111 1169 1095
267 279 262 257 252 263 111
200 0 77
13.9 3 16.6
19:27:06 1295 1288 1233 1208 1216 1172
270 282 264 261 255 266 113
123 0 77
13.9 4.9 16.6
19:27:12 1289 1299 1268 1242 1241 1215
274 285 266 264 259 270 115
84 0 77
13.9 7.8 16.6
19:27:18 1334 1331 1347 1346 1339 1315
281 293 269 273 266 280 115
32 0 77
13.9 27.6 16.8
19:27:24 1285 1298 1316 1328 1309 1310
291 305 277 287 279 293 113
43 0 77
13.9 28.3 16.8
19:27:30 1285 1298 1328 1334 1324 1324
299 316 286 299 290 305 113
49 0 77
13.9 28.8 16.8
19:27:36 1294 1310 1340 1347 1339 1332
306 325 294 309 299 314 113
53 0 77
13.9 28.8 16.8
19:27:42 1294 1310 1345 1347 1339 1332
312 334 302 317 308 323 113
53 0 77
13.9 28.8 17
19:27:48 1294 1310 1345 1347 1339 1332
317 342 308 324 313 330 115
53 0 77
13.9 29.2 17
19:27:54 1294 1310 1345 1356 1339 1332
321 349 314 331 319 336 115
62 0 77
13.9 28.3 17
19:28:00 1294 1310 1345 1356 1339 1332
324 354 319 337 323 342 118
62 0 77
13.9 28.3 17
19:28:06 1289 1310 1339 1356 1339 1332
327 358 323 342 326 347 120
67 0 77
13.9 28.6 17
19:28:12 1283 1304 1339 1356 1329 1332
330 362 326 345 329 352 123
73 0 77
13.9 28.4 17.2
19:28:18 1283 1304 1339 1356 1329 1321
330 365 328 348 332 355 125
73 0 77
13.9 28.4 17.2
19:28:24 1283 1304 1330 1347 1320 1321
332 367 328 350 332 358 129
64 0 77
13.9 28.4 17.2
19:28:30 1278 1293 1324 1342 1314 1312
332 369 331 352 335 360 132
64 0 77
13.9 28.4 17.2
19:28:36 1278 1293 1324 1342 1314 1312
332 369 331 352 335 362 135
64 0 77
13.9 28.6 17.4
19:28:42 1267 1293 1324 1334 1314 1312
332 371 331 354 335 362 138
67 0 75
13.9 28.4 17.4
19:28:48 1267 1284 1316 1334 1304 1301
332 371 331 354 335 362 140
67 0 75
13.9 28.4 17.4
19:28:54 1267 1279 1310 1328 1291 1295
332 371 331 354 337 364 140
61 0 75
13.9 27.3 17.4
19:29:00 1258 1274 1305 1328 1278 1283
332 371 331 354 337 364 140
70 0 75
13.9 26.8 17.6
19:29:06 1251 1267 1298 1316 1268 1278
332 371 331 354 337 364 142
65 0 75
13.9 27 17.6
19:29:12 1251 1267 1298 1316 1268 1273
332 371 331 354 337 364 142
65 0 75
13.9 26.8 17.6
19:29:18 1251 1260 1292 1316 1268 1273
332 371 331 354 337 364 142
65 0 75
13.9 27.2 17.6
19:29:24 1251 1260 1292 1311 1268 1268
334 371 333 354 337 364 145
60 0 75
13.9 26.7 17.6
19:29:30 1244 1260 1292 1311 1262 1268
334 371 333 356 335 364 148
67 0 75
13.9 26.7 17.8
19:29:36 1244 1255 1292 1311 1257 1268
334 371 333 356 335 364 151
67 0 77
13.9 26.7 17.8
19:29:42 1244 1255 1287 1306 1257 1268
334 371 333 356 335 364 155
62 0 77
13.9 27.1 17.8
19:29:48 1251 1260 1295 1311 1257 1279
334 371 333 356 335 364 155
60 0 77
13.7 26.3 17.8
19:29:54 1251 1260 1290 1311 1257 1273
334 371 333 356 335 364 158
60 0 77
13.7 26.5 18
19:30:00 1245 1260 1290 1311 1257 1273
334 371 333 356 335 364 158
66 0 77
13.7 26.5 18
19:30:06 1245 1260 1290 1311 1257 1267
334 371 333 356 335 364 160
66 0 77
13.7 26.5 18
19:30:12 1245 1255 1290 1304 1257 1267
334 371 333 356 335 364 162
59 0 75
13.7 26.5 18
19:30:18 1245 1255 1285 1304 1257 1267
334 371 333 356 335 364 162
59 0 75
13.7 26.5 18
19:30:24 1245 1255 1285 1304 1246 1259
334 371 333 356 335 364 165
59 0 75
13.7 26.5 18.2
19:30:30 1237 1248 1276 1304 1246 1259
334 371 333 356 335 364 165
67 0 75
13.7 26.5 18.2
19:30:36 1237 1243 1276 1296 1246 1259
334 371 333 356 335 364 167
59 0 75
13.7 26.5 18.2
19:30:42 1237 1243 1276 1296 1246 1259
334 371 333 356 333 362 167
59 0 75
13.7 26.3 18.2
19:30:48 1231 1243 1276 1296 1246 1259
334 371 333 356 333 362 169
65 0 73
13.7 26.7 18.4
19:30:54 1231 1238 1271 1290 1246 1259
334 371 333 356 333 362 169
59 0 73
13.7 26.5 18.4
19:31:00 1231 1238 1271 1290 1246 1259
332 369 333 354 333 360 169
59 0 73
13.7 26.5 18.4
19:31:06 1231 1238 1265 1290 1237 1253
332 369 331 354 331 360 169
59 0 73
13.7 26.5 18.4
19:31:12 1225 1233 1265 1284 1237 1253
332 369 331 354 331 360 169
59 0 73
13.7 26.5 18.4
19:31:18 1225 1233 1265 1284 1237 1243
330 367 331 351 329 360 171
59 -11 73
13.7 26.5 18.6
19:31:24 1218 1226 1259 1279 1232 1243
330 367 329 351 329 358 171
61 0 73
13.7 26.5 18.6
19:31:30 1218 1226 1259 1279 1232 1243
330 367 329 351 327 356 171
61 0 73
13.7 26 18.6
19:31:36 1218 1226 1259 1279 1232 1237
327 365 327 349 327 356 171
61 -10 73
13.7 26.5 18.6
19:31:42 1218 1226 1253 1273 1232 1237
327 365 327 349 327 356 173
55 -10 73
13.7 26.5 18.8
19:31:48 1218 1226 1253 1273 1225 1237
327 363 327 349 325 354 173
55 0 73
13.7 26.5 18.8
19:31:54 1208 1219 1246 1263 1225 1237
325 363 325 347 325 354 173
55 -10 73
13.7 26.3 18.8
19:32:00 1208 1214 1246 1263 1219 1232
325 361 325 347 325 352 173
55 0 73
13.7 26.3 18.8
19:32:06 1208 1214 1246 1263 1219 1232
325 361 325 345 323 352 173
55 0 73
13.7 26.5 18.8
19:32:12 1208 1214 1246 1263 1219 1232
323 361 323 345 323 352 175
55 0 73
13.7 26.2 19
19:32:18 1208 1214 1246 1263 1219 1232
323 361 323 345 323 352 175
55 0 73
13.7 26.2 19
19:32:24 1208 1214 1246 1263 1214 1232
323 361 323 345 323 352 175
55 0 73
13.7 26.2 19
19:32:30 1208 1208 1246 1263 1214 1224
323 361 323 345 323 352 175
55 0 73
13.7 26.4 19
19:32:36 1208 1208 1241 1257 1214 1224
323 361 323 345 323 350 175
49 0 73
13.7 26.1 19.2
19:32:42 1202 1208 1241 1257 1214 1224
323 361 323 345 323 350 177
55 0 73
13.7 26.3 19.2
19:32:48 1202 1208 1236 1251 1209 1224
321 361 323 345 321 350 177
49 0 73
13.7 26.3 19.2
19:32:54 1202 1208 1236 1251 1209 1218
321 361 323 345 321 350 177
49 0 71
13.7 26.3 19.2
19:33:00 1197 1203 1236 1251 1209 1218
321 361 323 343 321 350 177
54 0 71
13.7 26.3 19.2
19:33:06 1190 1190 1223 1241 1191 1201
321 361 323 343 321 350 177
51 0 71
13.7 24.5 19.4
19:33:12 1190 1197 1223 1241 1183 1195
321 361 321 343 321 350 177
58 0 71
13.7 23.6 19.4
19:33:18 1197 1197 1231 1241 1183 1195
321 359 321 343 319 348 177
58 0 71
13.7 23.6 19.4
19:33:24 1197 1197 1231 1241 1183 1195
319 359 319 341 319 348 177
58 -12 71
13.7 23.6 19.4
19:33:30 1197 1197 1231 1241 1183 1195
319 359 319 341 319 346 177
58 0 71
13.7 22.9 19.4
19:33:36 1213 1219 1249 1265 1198 1212
319 359 319 341 317 346 177
67 0 71
13.7 22.6 19.6
19:33:42 1218 1219 1249 1271 1205 1217
319 359 317 339 315 346 177
66 0 71
13.9 22.6 19.6
19:33:48 1223 1225 1249 1271 1205 1217
317 359 317 339 315 344 177
66 0 71
13.9 22.6 19.6
19:33:54 1223 1225 1249 1271 1205 1211
317 359 317 337 315 344 175
66 -10 71
13.9 22.6 19.6
19:34:00 1223 1225 1249 1271 1205 1211
317 357 315 337 313 344 175
66 0 71
13.9 22.6 19.6
19:34:06 1223 1225 1249 1271 1205 1211
315 357 315 337 313 342 175
66 0 73
13.9 22.6 19.8
19:34:12 1218 1225 1249 1271 1205 1211
315 357 313 335 311 342 175
66 0 73
13.9 22.6 19.8
19:34:18 1218 1225 1249 1271 1205 1211
315 357 313 335 311 340 175
66 0 73
13.9 22.3 19.8
19:34:24 1218 1220 1249 1271 1205 1211
315 355 313 335 309 340 175
66 0 73
13.9 22.3 19.8
19:34:30 1218 1220 1249 1271 1205 1211
315 355 311 333 309 340 175
66 0 73
13.9 22.5 19.8
19:34:36 1218 1220 1249 1271 1205 1211
313 355 311 333 309 338 173
66 0 73
13.9 22.5 19.8
19:34:42 1256 1259 1284 1309 1243 1252
313 355 311 333 309 338 173
66 0 73
13.9 20 20
19:34:48 1340 1340 1362 1387 1318 1333
315 355 311 333 309 340 173
69 0 73
13.9 18.4 20
19:34:54 1357 1358 1385 1405 1341 1349
315 355 311 335 311 340 173
64 0 73
13.9 18.4 20
19:35:00 1363 1364 1385 1405 1341 1349
317 357 311 335 313 342 173
64 0 73
13.9 18.4 20
19:35:06 1363 1364 1385 1413 1341 1355
319 357 313 337 315 344 173
72 0 73
13.9 18.4 20
19:35:12 1363 1364 1385 1413 1341 1355
321 359 315 337 315 344 173
72 0 73
13.9 18.4 20
19:35:18 1363 1364 1390 1413 1341 1355
321 361 317 339 315 346 173
72 0 73
13.7 18.4 20.2
19:35:24 1363 1364 1390 1413 1341 1350
324 361 317 339 318 348 173
72 0 73
13.7 18.4 20.2
19:35:30 1363 1364 1390 1413 1341 1350
324 361 317 341 318 348 173
72 0 73
13.7 18.4 20.2
19:35:36 1363 1364 1390 1413 1341 1350
326 364 319 341 320 351 173
72 0 73
13.7 18.4 20.2
19:35:42 1363 1364 1390 1413 1341 1350
326 364 321 343 320 351 173
72 0 73
13.7 18.4 20.2
19:35:48 1363 1364 1390 1413 1341 1350
328 366 321 343 322 353 173
72 0 73
13.7 18.4 20.2
19:35:54 1356 1364 1390 1413 1341 1350
328 366 321 343 322 353 173
72 0 73
13.7 18.4 20.2
19:36:00 1356 1364 1390 1413 1341 1350
328 366 321 345 322 353 173
72 0 73
13.7 18.4 20.4
19:36:06 1356 1364 1390 1413 1341 1350
330 368 323 345 324 355 173
72 0 73
13.7 18.4 20.4
19:36:12 1356 1364 1390 1413 1341 1350
330 368 323 345 324 357 173
72 0 73
13.7 18.4 20.4
19:36:18 1356 1364 1390 1413 1341 1350
332 368 323 345 324 357 173
72 0 73
13.7 18.4 20.4
19:36:24 1356 1364 1390 1413 1341 1350
332 370 325 347 324 357 173
72 0 73
13.7 18.4 20.4
19:36:30 1356 1358 1385 1405 1341 1350
332 370 325 347 326 357 173
64 0 73
13.7 18.4 20.4
19:36:36 1356 1358 1385 1405 1341 1345
332 370 325 347 326 359 173
64 0 73
13.7 18.4 20.6
19:36:42 1349 1358 1385 1405 1341 1345
334 372 327 349 326 359 173
64 0 73
13.7 18.4 20.6
19:36:48 1349 1352 1385 1400 1336 1345
334 372 327 349 326 361 173
64 0 73
13.7 18.4 20.6
19:36:54 1349 1352 1379 1400 1336 1345
334 372 329 351 329 361 173
64 0 73
13.7 18.4 20.6
19:37:00 1349 1352 1379 1400 1331 1345
336 374 329 351 329 361 173
69 0 73
13.7 18.4 20.6
19:37:06 1349 1352 1379 1394 1331 1340
336 374 329 351 329 363 173
63 0 73
13.7 18.4 20.6
19:37:12 1342 1346 1372 1394 1331 1340
338 374 331 353 329 363 173
63 0 73
13.7 18.1 20.6
19:37:18 1342 1346 1372 1394 1331 1340
338 376 331 353 331 363 175
63 0 71
13.7 18.3 20.8
19:37:24 1342 1346 1372 1394 1326 1340
338 376 333 353 331 365 175
68 0 71
13.7 18.5 20.8
19:37:30 1342 1346 1372 1394 1326 1332
340 378 333 355 331 365 175
68 0 71
13.7 18.5 20.8
19:37:36 1342 1338 1372 1394 1326 1332
340 378 333 355 333 365 175
68 0 71
13.7 18.5 20.8
19:37:42 1337 1338 1372 1394 1326 1332
340 378 333 355 333 365 175
68 0 71
13.7 18.3 20.8
19:37:48 1337 1338 1372 1388 1326 1332
340 378 333 355 333 365 175
62 0 71
13.7 18.5 20.8
19:37:54 1337 1343 1363 1388 1326 1332
340 378 335 357 333 365 175
62 0 71
13.7 18.5 21
19:38:00 1337 1343 1363 1388 1321 1332
342 378 335 357 333 365 175
67 0 71
13.7 18.5 21
19:38:06 1347 1353 1380 1401 1334 1340
342 378 335 357 333 365 175
67 0 71
13.7 17.3 21
19:38:12 1420 1420 1444 1456 1407 1412
342 378 335 357 333 365 177
49 0 71
13.7 15.2 21
19:38:18 1446 1438 1456 1456 1443 1445
342 378 335 357 333 365 177
18 0 71
13.7 15 21
19:38:24 1446 1438 1456 1444 1453 1453
342 378 335 355 333 365 177
18 0 71
13.7 14.5 21
19:38:30 1446 1425 1448 1437 1453 1446
340 378 335 352 333 365 177
28 0 71
13.7 14.5 21
19:38:36 1446 1425 1448 1437 1453 1451
340 376 335 350 333 365 177
28 -10 71
13.7 14.5 21
19:38:42 1431 1402 1433 1418 1448 1438
340 376 333 348 333 365 177
46 0 71
13.7 14.2 21.2
19:38:48 1453 1435 1453 1438 1457 1452
340 374 333 348 333 365 177
22 -19 71
13.7 15 21.2
19:38:54 1458 1446 1467 1461 1457 1452
340 374 331 348 333 365 177
21 0 69
13.7 15.4 21.2
19:39:00 1448 1439 1467 1470 1440 1440
340 374 331 348 335 367 177
31 0 69
13.7 15.6 21.2
19:39:06 1448 1439 1462 1470 1432 1432
342 377 333 350 335 367 177
38 0 69
13.7 16.1 21.2
19:39:12 1434 1432 1462 1470 1422 1426
342 377 333 350 337 369 177
48 0 69
13.7 15.5 21.2
19:39:18 1453 1448 1473 1470 1446 1445
342 377 335 350 337 369 177
28 0 69
13.7 15 21.2
19:39:24 1453 1441 1461 1451 1456 1450
342 377 335 350 337 369 177
20 0 69
13.7 14.3 21.2
19:39:30 1447 1424 1452 1437 1456 1450
342 377 335 350 337 369 177
32 0 69
13.7 14.3 21.4
19:39:36 1447 1419 1452 1432 1456 1450
342 377 335 347 337 369 177
37 -11 69
13.7 14.6 21.4
19:39:42 1457 1446 1467 1457 1456 1450
342 377 333 347 337 369 179
21 -11 69
13.7 15.2 21.4
19:39:48 1457 1446 1467 1466 1445 1450
342 377 333 347 337 369 179
22 0 69
13.7 15.4 21.4
19:39:54 1437 1433 1467 1466 1425 1428
342 377 333 347 337 369 179
42 0 69
13.7 16 21.4
19:40:00 1437 1433 1459 1466 1417 1419
342 377 333 347 337 369 179
49 0 69
13.7 16 21.4
Message 14
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
Jon Boede wrote:
> --> Yak-List message posted by: "Jon Boede" <jon@email.net>
>
> Ok, Brian... you talked me into it. What flavor of EGT gauge do you like,
> and where precisely did you mount it?
That is up to you. In terms of robustness and reliability Alcor is hard to beat
but they are more expensive. If you are on a budget, Westach stuff is cheap
and works just fine. Just be aware that the Westach probes will probably fail
every year or so. But when the Westach probe fails you can replace it with
an Alcor probe since probes are thermocouples and they all work the same. The
differences are mechanical.
And before someone gets on my case, yes, there are two common types, J and K.
EGT probes are K-type thermocouples. J-type are used for lower temperatures
and are often used for CHT measurement.
Chief aircraft has a a 2.25" Alcor EGT for $225. They have a Westach EGT for $64.
The UMA EGT that I had in my CJ6A costs $85. So you can see, if you can
afford to put gas in your airplane you can afford an EGT gauge, even the expensive
one.
Since you are just getting a relative indication you can put the probe anywhere
it is convenient. Mine was in the exhaust manifold between cyls 7 and 8 as I
recall. The indicator is just placed someplace convenient on the panel. Mine
went in place of the carb inlet air temp gauge at the bottom of the panel and
I moved the inlet air temp gauge someplace else since that gauge is pretty useless
but I didn't want to get rid of it either.
> And to think that my wife said there's nothing I wanted for Christmas. :-)
Happy to oblige!
--
Brian Lloyd 6501 Red Hook Plaza, Suite 201
brian@lloyd.com St. Thomas, VI 00802
+1.340.998.9447 - voice +1.360.838.9669 - fax
GMT-4
Message 15
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| Subject: | Re: CJ6A mixture (Was: MAP and RPM) |
--> Yak-List message posted by: Brian Lloyd <brian@lloyd.com>
Ron Davis wrote:
> --> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
>
> I'm sure you meant to say that horsepower = (torque X RPM) divided by 5252
Actually it depends on what units you use for torque, RPM and power. Torque can
be foot-pounds, newton-meters, dyne-cm, etc. RPM can be revs per minute, revs
per second, etc. The point is, power is torque times RPM. OK, throw in a
constant that makes the units come out right.
> What is metric horsepower? I've never come across that term. The metric
> system properly uses KW for engine power, but they often list horsepower
> too. I wasn't aware that there was a "metric horsepower" that was different
> from ours (technically, I think horsepower was a British invention- but it's
> ours now).
Here are the various horsepower figures specified in watts:
735.4988 W = 1 metric (French) HP
745.7 W = 1 British (UK) HP
746 W = 1 electric HP
746.043 W = 1 water HP
Don't you just love standards!
--
Brian Lloyd 6501 Red Hook Plaza, Suite 201
brian@lloyd.com St. Thomas, VI 00802
+1.340.998.9447 - voice +1.360.838.9669 - fax
GMT-4
Message 16
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--> Yak-List message posted by: cjpilot710@aol.com
Brain,
Are you heading this way? Inquiring minds wonder.
386-467-3313 home
Jim Goolsby
"They that can give up essential liberty to obtain a little safety,
deserve neither liberty nor safety"
Benjamin Franklin 1759
"With my shield, or on it"
Trojan Warriors BC
"The reason older men are like fine wine. When young, they are like grapes
until some woman stomps all over them."
Unknown older man.
Message 17
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| Subject: | Re: Lean Vs. Rich (was MAP and RPM) |
--> Yak-List message posted by: "Walt Lannon" <lannon@look.ca>
Thanks for a very timely and accurate explanation of the LOP/ROP question.
With regard to radial engines only (with their close to optimum mixture
distribution) it is fair to say that LOP operation is perfectly acceptable.
As mentioned by other posters this was standard operating procedure for all
airlines in the good old days of round engine airliners. I think this was
refered to as "best economy" and though operating at slightly less than best
power resulted in lower seat/mile costs with no detrimental effects to the
engines.
The CJ6 throttle/mixture system is a direct copy of the British standard
that provided a "safe" method of throttle operation to prevent an
inadvertant excess lean condition with throttle reduction (ie: throttle
back enriches mixture). Probably thought to be prudent for training and
combat operations. This is one of the major differences between the T6 and
Harvard versions of the outstanding North American trainer of WW2.
The Harvard uses the British mixture control of "rich - aft' but with a
removeable latch to accomodate the idle cut-off feature of the American
carburettor (in British carburettors this was a seperate control). This
moveable latch also allows mixture adjustment ahead of the throttle. Having
flown the Harvard for more than 25 years and with an EGT guage installed I
have found that up to approx. 10,000 ft. the mixture control on the throttle
stop will yield an EGT of 25 to 50 degs.F ROP. I used to fine tune it ahead
of the throttle to LOP to optimize fuel consumption but found it wasn't
worth the trouble and the constant attention needed with any altitude
changes.
Whether the CJ system works as well I don't know (since my own is still a
hangar queen and the others I have the opportunity to fly are mostly short
flights) but I suspect it is very dependant on the correct adjustment of the
carburettor and therefore may vary greatly between aircraft.
What is the point of this diatribe? Beats the hell out of me but maybe it's
just to say fly safe, if you want to save fuel do it right. Make sure your
carb. is properly adjusted and you know how to lean correctly, particularly
if you have removed the mixture/throttle stop.
Cheers;
Walt
----- Original Message -----
From: "Womens Specialty Care ObGyn" <drc@wscare.com>
Subject: Yak-List: Lean Vs. Rich (was MAP and RPM)
> --> Yak-List message posted by: "Womens Specialty Care ObGyn"
<drc@wscare.com>
>
> Lean of peak EGT vs. Rich of peak EGT
>
> For a very detailed and excellent explanation of the two options see the
GAMI injector site.
>
> But I will try to summarize.
> There is an ideal mixture for optimum combustion rate in the cylinder
(stochiometrics for any chemistry buffs)
>
> For T.O. we all operate traditionally at full rich (more gas than air as
it relates to the ideal mixture) then we lean once cruise power is set. as
we lean and get close to the ideal mixture HP increases and so does heat as
the mixture is more efficiently burned. Then the ideal mixture and max
power output is reached as signaled by the peak EGT. If we continue to lean
then HP decreases, fuel flow decreases and temps decrease. The HP and temp
falls off faster than it rises on the "rich " side of the curve.
>
> Because of the steep fall off on the "lean" side of the curve fuel flow
becomes critical and if the fuel flow is not balanced well to all cylinders
then the engine seems to run rough - which we have all experienced. This is
the principle behind making variable size injectors to keep the fuel flow
similar in all cylinders. This is what GAMI's do - particularly for the
flat Continental engines because of the asymmetric fuel distribution system
on the top of the engine. Historically manufactures recommended rich of
peak to keep the engine running smooth and cool. Now with differential
injectors we can keep the engines running smooth and cool on the lean side
of peak.
>
> Hope that helps - more details are available with the graphs at the GAMI
site.
>
> HerbC
>
>
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