[ImprezaRS]

Originally Posted by Moai

in short, yes.

brew is correct. colder air = denser air. therefore there will be more air per unit volume as opposed to air at a warmer temperature. In turn, the air/fuel ratio will be higher. How much higher depends on the temperature.
For instance, you may experience knock on a car at 15psi on a 30 degree day, which you wouldn't see on a 70 degree day.

enough said