Originally Posted by Mike Benvo
The colder the better to an extent. It becomes a balance of the variables.
There is no "magic" number.
You have to look at:
1. Air Density (colder air = denser air = more oxygen available for combustion) End result is ECU runs more timing and car makes more power. The difference between very cold and very got can be a significant amount of horsepower.
This, plays into the same thing with flying you get better power, lift and bite out of the prop due to the denser air.
No doubt the M loves the cold air and the sound is just terrific. My bike with the Akra on it sounds menacing as well, but the tires that I have on it don't like the cold weather so much...