What kind of racing are you doing? Putting headers on a street machine is a waste of time, money, and effort, particularly on a big block in a stovebolt truck. You'll seldom, if ever get the RPM high enough to benefit from using headers instead of stock exhaust manifolds.
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!