Originally Posted by Hemi_Joel
I agree airflow is a likely culprit with the circumstance you describe. But not for certain:

If it has an automatic trans, the heat generated from the converter due to the high idle of a cammed up engine and/or a loose converter can cause the coolant temp to rise from the trans cooler in the radiator. I recommend testing by installing a remote trans cooler and disconnecting the one in the radiator. Or you can drive in traffic and keep popping it into neutral when you are on the brakes to reduce heat from the trans and see if that helps.

Also, what is your timing at idle and off idle, at the RPM that the overheating occurs? It should be at least 20, preferably more, and if you have a operating vacuum advance hooked up to manifold vacuum, that helps too.


This ... auto trans ?? If so what is your convertor stall ? Where is your trans cooler , and do you have an auxiliary cooler also , factory hemi /auto trans cars did .

Also you said 35 total , is that what it runs best at ? I've been watching a lot of auto related tech these days and the 2nd gen hemis are said to not need as much total as a wedge headed engine ???

running up my post count some more .