I thought this was interesting about the heads. A few years ago I asked a Stock Elim. racer about the NHRA Edelbrock heads he had on his 340. He told me the heads were approved because usable original cast iron heads were getting harder and harder to find, and that the NHRA had approved a replacement aluminum head for the Chevy's several years before that. He also told me he had to put the weight savings from the aluminum heads back onto the FRONT of his car. Did the NHRA already approve an aftermarket intake for the Chevy's too? I dunno.
