What kind of racing are you planning to do? Is that increased lift on the intake or the exhaust valves? Porting a stovebolt head is approximately as effective as shoveling sand down a groundhog burrow.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!