"EGT, O2 (A/F) Tuning, Etc."

[UBFJ #454]

We use both to tune ... And/Or ... Monitor Our Motor ...
Let's start a discussion here on how to best use these devices (and Others) to get the best Results ... Realizing, And Respecting, Different 'Tuners' Use Different Methods based upon their Experience.

[Morg]

Excellent topic.
I'll stick my neck out & throw a theory out there. I'm thinking you would need to find which cylinder is getting the most heat. Then tune to that cylinder?
I am looking for a small EGT that has memory. Maybe just an electronic readout. Any sugestions?

[21rayson]

Excellent topic.
I'll stick my neck out & throw a theory out there. I'm thinking you would need to find which cylinder is getting the most heat. Then tune to that cylinder?
I am looking for a small EGT that has memory. Maybe just an electronic readout. Any sugestions?
lavorsi makes a good one i'm going to use in my turbo boat it will monitor both banks and read the hottest side and it has recall. the size is 3 5/8 dial read out anlog there's more too it.

[Morg]

Thinking of something like This (http://www.dynotunenitrous.com/store...?idproduct=134)
If it had memory it would be pretty much what I am looking for.

[Fiat48]

Computech has a good one. Have used them for years with no problems. I use single probe clamp on. http://38.113.97.153/products/Computech/da01a.asp
You're welcome to borrow mine to get a reading. Only a small hole needed in the header. No welding required.

[Unchained]

I use an O2 sensor and I have an EGT thermocouple also.
I use the O2 sensor mainly. I find that if I adjust the cruising speed ( 3000 rpm / 12" vaccuum ) A/F ratio to 14.5:1 the EGT will be 1650 +. I've run it this way for long durations with no problems and the plugs read real good. If I adjust down to 12.5:1 A/F ratio it will drop the EGT down to 1450 but then I'm not at Stoichiometric and I'm dumping in fuel that won't be burned. I tend to ignore the EGT and go with the O2 sensor and tune to Stoich.
At WOT or anything less than 1" vaccuum I have the fuel maps tuned at 12.3:1 for max power.
Jak, You guys have been using an O2 sensor ? Do you have it in one side or both
headers ?

[Morg]

Hey Bob,
Just looking at the one you linked. Does it have a recall?
Also, I know the EGT is placed 2" out. Where is the o2 sensor placed, collecter?? & on that note I know Unchained likes the o2, whats the census, o2 or EGT or both?

[Fiat48]

Mine is an older unit and it has recall. You'd have to make sure on the new one. Probe goes about 1 1/2" out from the header flange on the pipe of the cylinder you want to read.

[MESA BALANCING]

What we use in here in the shop is the exhaust temp and a o2 sensor in all the pipes to isolate lean conditions in any cylinders it's expensive but worth every penny you'd be suprised how much power you can gain from stagger jetting the carbs in some cases and also for the efi stuff. SIncerely yours Laz

[Unchained]

What we use in here in the shop is the exhaust temp and a o2 sensor in all the pipes to isolate lean conditions in any cylinders it's expensive but worth every penny you'd be suprised how much power you can gain from stagger jetting the carbs in some cases and also for the efi stuff. SIncerely yours Laz
Sounds like the way to go for dyno tuning. Have you found much differences between cylinders with EFI port injection ?
During a dyno tune are you able to duplicate part throttle cruising conditions and tune at 14.7:1 A/F ratio ? What did you get for EGT's ?
I know that EGT's are highest at Stoichiometric.
Morg, the O2 sensor would normally go in the collector. It has to be dry. It seems like someone could use an old header and run it dry for a session of A/F ratio tuning.