From what I understand, exhaust gas tempratures are directly related to the A/F ratio. Does anyone have a chart that correlates the the two? I'm looking for a chart that will say, for example, 250 degrees F on the EGT is equal to X on the A/F. Thats what I'm looking for.

Thanks,

 

Well the only AFR's that you shoudl rely on are those taken from a wide band sensor. I don't know of any chart that plots the two together. I would not think they correlate TOO much because different things may affect the EGT like ambient temps and such.

 

Not always true.

Advancing ( or retarding ) timing while keeping the same A/F ratio can dramtically effect EGT's

 

problem with EGT is it's not as fast as a wideband from what i understand.. basicaly my car has both now.. the GReddy EGT and a techedge wideband setup... once i start tuning i'll post results of how similiar it is.

 

Timing can and will have a greater efefct on EGT than A/F.

Daniel

 

They are not related that much. So many factors effect your EGT. Things like Ambient temps, intake temps, gas quality, air flow around your engine bay, and many other things. AFR is read as a Ratio. Egt is just anouther lil gauge to chunk money at. IMOP.

There is one place you would catch me using an EGT. Piston powered airplanes.


JAmes

 

EGT's can be useful if you know how to tune with them, but I would reccommend a wideband over an EGT for tuning.

 

I know this sounds basic, but the AFR gauge is for tuning to an AFR, and the EGT gauge is for tuning to an EGT. Each will give you an indirect indication of the other, but there are other factors involved that make the indirect reading less accurate than the proper direct reading. The problem is that many people on this forum think that the AFR gauge is used to maintain "safe" engine tuning in order to combat detonation. However, detonation is primarily a temperatue issue, which is better monitored by EGT and MAT. The AFR reading will help reduce tuning time on the dyno, and is good for tuning transients like acceleration enrichment. Both EGT and AFR can be used to tune for power.

Show me a turbine engine with an O2 sensor.

 

Actually, the Metro which uses a Garret engine does use an EGT gauge. Not for the reasons we do. So you do not melt your engine.

But yeah.......no O2 sensor

James