Newps

JGalban via AviationKB.com wrote:
> Newps wrote:
>> Temp has almost nothing practical to do with the octane required. What
>> matters is the internal cylinder pressure.
>
> I agree that cylinder pressure is the primary factor, but intake
> temperatures can push detonation margins lower. That's why intercoolers and
> water injection systems were invented.

Yes, but raise the temperature of the air and you lower its density
altitude which reduces the octane requirement. So temp plays a factor
but it's a complex relationship.