EGT for mixture setting

[Darrell Norquay]

Ed Hernandez wrote:

> A very conservative method would be to tune A/F for the same EGT at 
> WOT across the rpm range. A more aggressive approach would be to tune 
> A/F for a shallow but constant rising slope vs rpm. There are lots of 
> ideas as to a maximum EGT which you shouldn't exceed. Some like to
> use about 1800 F on dyno, but that's pretty short term. I love it when
> the exhaust glows red!

Does the EGT sensor have to be close to the head?  The reason I ask is 
that I have headers, and the only practical place to mount EGT's would be
in the collectors.  I assume that the temperatures would be somewhat 
reduced, but still proportional(?)

How does the mixture affect EGT?  Do lean mixtures produce lower or higher 
temps than rich ones?  
 
Can you determine if you are at stoich with this method (with any accuracy)?
Is there a linear relationship between EGT and AFR or is it a complex 
function?

Is this a practical/effective/reliable way to adjust mixture?  Is it only 
useful at WOT, or does it maintain some validity at all throttle settings?

What other factors affect EGT?

regards
dn

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 Darrell A. Norquay              Internet: dn at dlogtech.cuc.ab.ca     
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