A cooler motor tends to run better, but alot of the power of a head comes from the dome size, if you are running a stock size dome it will cool your motor alot better but might only give min imal results to power, with that said if you were to change your dome size and higher compression you should get a increase of power...and with that being said lol your power might have acost in the fuel department b/c if you get to greedy with compression you generally should run higher octane fuel.