"Morgans" wrote in message
...

"Kyle Boatright" wrote

Double? Naah. It expands, but doesn't double. Boyle's law (PV=NRT) is
based on absolute temperature, which is measured in kelvin. Kelvin is
Celsius plus 273 degrees. Guessing now, if the air temp went from 300k to
350k (or about 80F/27C to about 160F/70C) you'd see volume increase by
(350/300 -1) = 1/6th = about 17%...

OK. I have always heard the approximate rule for good cooling is double
the intake size for the exit size. Guess it doesn't transfer to
expansion.

Thanks for the info on the air expanding. Does this translate into more
drag if the engine is running?

Danny Deger