EGT monitoring

[David G]

I rigged up a little arduino project for EGT.

It has 4 channels and will talk can bus to the computer on my MH44 EFI.

I plan to put the carburetor back on and get baseline numbers.

 

[4play]

Is this strictly for monitoring purposes?

 

[David G]

I will use it for tuning.

I want to see the differences in EGT between the cylinders, then vary the injection timing and compare.

 

[CenTex Farmall]

Are you running an O2 sensor as well?

 

[David G]

Just a single common one, thermocouples are a lot cheaper.

 

[CenTex Farmall]

O2 vs. EGT would be an interesting plot. Rich of peak or lean of peak always started some good arguments at the airport.

 

[David G]

I always leaned after peak during cruising.

 

[CenTex Farmall]

I started in the rich of peak crowd and then defected to the lean of peak crowd after I had learned more and had gained some wrench time as well.

 

[David G]

You a pilot?

 

[CenTex Farmall]

Yes, I'm "retired" though.

 

[Geo-TH,In]

David,
I put an EGT on the muffler of my Jubilee. I found the temp will vary with RPMs, load and the fuel to air ratio. I adjusted my carb for peak in second gear, 1800 RPMS while mowing with a 72 inch woods finish mower.

Then in the winter, engine wanted more fuel so I had to crank main jet out.

I would think for best results you may need to come up with a constant load over different RPM ranges.

Not sure how many fuel injectors use EGT alone. Good luck, Post back with findings. geo

 

[David G]

My wife worked for Air Force in NM, I got to do a lot of mountain flying when we lived there, have not flown since we left 21 years ago. It takes a pilot to talk about leaning after peak EGT.

 

[David G]

I plan to put it on constant load with dyno and vary the injector timing and see what it does. I would anticipate that the two inner cylinders will run rich and outer lean. I want to bolt the old carburetor back on and see how that compares. I really have no clue on what the temperature variance will look like.

 

[CenTex Farmall]

I'm guessing yall were in the Albuquerque area. I've been into Roswell and Santa Fe numerous time but not over to ABQ. I haven't been in a recip in well over 10 years. Around '01 I traded EGT for ITT.