Cylinder heads, everybody has "a guy" that does heads. Can you find a guy to do a set of heads for five or six hundred bucks? Yeah probably. When you do, ask him what kind of performance you should expect with his head work. If he gives you a hp number close to the number of cubic inches your motor displaces walk away. In fact the next time you talk to that guy ask him if he helped set any land speed records. When you get the blank stare you'll know where to go.
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