Originally Posted by wwest (Post 99815)

Picking nits but...

Your actual wording was/is....

"It dumps a small amount of heated air mixture back in the intake manifold on the combustion stroke."

First, I was trying to correct your statement that it was the COMBUSTION stroke wherein A/F mixture is dumped (pushed) back into the intake manifold when actually it is done during the compression stroke. And since you mistakenly said combustion stroke, were that true, then ordinarily the A/F mixture would have been heated by compression.

So I went overboard, sorry.

It doesn't matter, the A/F mixture is pushed out before the combustion stoke and or compression stroke, they are the same.

And..

If it is so greatly desireable to have warmer airflow for FE during part throttle then do you mean to imply that all these folks modifying the intake path with "cold air boxes" are just wasting their money?

It depends on what you are trying to accomplish. Colder air expands more and gives you a bit more compression. In my racing days when FE was not the goal, I wanted as much cold air as possible.

If a warmer airflow were to be desireable for FE that why would the manufacturing companies be making such an obvious effort to place airflow intake upstream of the radiator? Under your theory the engine airflow intake should be downstream of the condensor/radiator assembly.