but in actuallity you can run hotter running rich too.............relative to leaning out though it's cooler.

 

FWIW I had a timing issue once that caused my headers to glow bright red. I am pretty sure I had a rich condition rather than a lean condition because I could actually see and hear the flame coming out of my tail pipes.

 

There's always a lot of confusion on this issue.

You can take any engine, tune it perfectly in regards to A/F ratio and timing, look at the EGT and record it.
Now back the timing way off and watch what happens to the headers.... they'll start to glow.

A/F ratio is still unchanged. What has changed is when and where the combustion takes place. Late timing means that a good deal of the combustion process is being blown out into the header primary and things get real hot when that happens. A thermocouple/EGT setup may not be the best way to measure what's going on here because of the placement.... especially considering a big part of the combustion is happening somewhere downstream like in this example.

The worst case scenario would be: too much timing delay and too much fuel (rich). But either/or will make the header primaries glow. Lean mixtures are hotter in the combustion chamber... valves run hotter and the EGT's measured right at the exhaust port are usually higher all things considered equal.

-Mindgame

 

That there is. You got it right but I'll quote El Chucko also-

 

Mindgame i love your avatar....

 

Chuck knows a few things about engines eh?

Well thanks Dave!

You a BSD fan or are you just saying the "demon" fits me?

-Mindgame