383 Build - Help!

BBBCUDA said

I don't see an over bore stamp on the piston tops, so I will assume it's standard bore. With a .039" gasket, and a .020" below deck, (might be more), the +5 cc valve notches make 9.06 to 1 compression if the heads are indeed 78.5 cc's. Nows the time to cc some stuff before it goes together, in case you want to have some things milled.

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There is a 40 stamped on the bottom of the piston in the pic so I would assume .040 over bore. Everything looks to be balanced due to the drill marks under the pistons. I agree they are below deck. I'm thinking around 8.6:1 with a Felpro Blue.

FYI,
my 400 is 0-deck with notched flat tops and 906 heads @88cc's.
9.0?:1 compression with .060 MLS headgaskets.

Hey matthon,
that low deck is gonna need to spin some rpm's to benefit from that tunnel ram. Your cam choice will need a broad rpm range. I would ditch the ram and put a M1 or RPM intake on it with a quality 4150 style 750. It WILL run better! If you want something to stick out of the hood find you a 8-71 supercharger for it. The compression ratio is ideal I bet.
Be sure to clean that engine thoroughly before assembly. Use some diesel or kerosene with a parts brush then blow it out. That brown preserver needs to be removed. Looks like a decent pump gas street setup. Stay away from the VOODOO cams! Garbage! A lot of the cams offered for Mopars are Chevy grinds. I would stick to the Purpleshafts or move on to a Scott Brown custom ground cam. Your choice though! Depends on your pocketbook. Looks like the heads have double springs so I would stick with a cam below .500 lift. Honestly I would choose a cam, lifter and spring kit to be safe.

N/A you should be good for 375-400 horses with the right cam and induction.
Just my 2 cents.