Quote:
Originally Posted by RETed
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Some of the info on that page is incorrect or misleading.
First, it is correct that the EGT numbers are meaningless without finding mean best torque on your particular motor first. This will give you an idea of what the EGTs
should be under ideal conditions and full load.
After that, the relationship between timing and EGT and AFR and EGT gets cloudy.
Advancing the timing will only lower EGTs if the actual combustion event is already late (i.e. - peak pressure happening after 20° ATDC or so).
If the peak pressure is early (detonation, which may NOT be audible), advancing the timing will makg the EGTs go up.
If you have found the MBT AFR reading, making the mix leaner will raise the EGTs to a point, but then they will start to go down again once you start to lean misfire (which may NOT be audible or even noticible in normal driving).
Making the mix richer
may lower EGTs, but only to a point.
Once you start to get rich misfires, the EGT will start to climb quite suddenly and any fuel that doesn't meet O2 in the combustion chamber might cause manifold combustion which will do CARAZY things to the EGT (up, down, fluctuating, who knows).
All that said, 1800°F - 2000°F right at the ports on a boosted rotary application is not too unusual.