Here's what I would do...250 crank, and flat top pistons..(you DO NOT want dish pistons) and have the head shaved if you can...had .030 shave off my 292's head...also 0 decking the block will help with more compression. A mild cam will improve majorly and as far as the head I'd do a lump port conversion, 1.86 intake and 1.60 exhaust valves. 4 barrel and headers...can't say hp specs but can say the improvement is noticeable for sure. Have you considered just purchasing a 250 for more cubic inch? A naturally aspirated 250 I've seen make 310 hp.
Last edited by TJ's Chevy; 04/01/15 11:41 AM.
