Cooler Temps Question

[RBS]

I was talking with a friend of mine the other day, telling him that I'm going to be jet-hotting my long tube headers. He then asked me a really profound question: Why do cars run better when they're cooler?

To be honest, I was taken back. I've always known that cars perform better under cooler conditions and temperatures - but why?? Over the past year, I've spent tons of money on a CAI system, electric fans, and jet-hotting - but I don't have the foggiest as to the technical reasons!

I'm sure that the answer is simple - but could someone help me out here?

Thanks!

 

[BigBlackQC]

Cooler air is denser air. Denser air combined with more fuel to maintain an equal air/fuel ratio equals more power. This is why lower intake temps improve hp and tq. As far as the engine running cooler, it will allow for a little more timing advance without having pre-ignition, the timing advance will create more power for you.

 

[SilvrSRT10]

Cooler air is denser. This allows more air into the cylinder giving you more power. This is why you see some drag racers icing the intake manifold between runs so that it doesn't heat the air. Nitrous also has the same affect along with the additional oxygen.

 

[LitemUp]

Yeah, what theysaid.