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Re: Big Block Crank Swap Question

From: Dave Bingaman
Remote Name:
Date: October 02, 2003


My understanding is that swapping pre 62 cranks into post 62 engines is completely do-able. Think about this. Take your 383RB crank and slip it into a 400B block and get 452ci with its copius amounts of ground pounding torque to move the older & heavier FLs and a lighter engine to boot. Some slight mods to the bottom of the engine so the crank throws clear and turning down the main journals are mostly what is necessary along with rod change. The RB cranks had a bit larger mains than the B cranks, so they need to be turned down to fit in the B blocks. What I am not sure of is the engine mount bosses on the newer (post '65) B/RB engines and if they would fit the older mounts. In 1965 there was a change in engine mount location (they pushed it back further towards the firewall for better weight distribution) and I have read of problems in swapping blocks. With this, you could keep your old tranny, but you may need to beef it to handle additional power.


Last changed: July 19, 2018