Try to find a 472 or 500 cubic inch Cadillac engine and a Turbo 400 transmission from a mid-1970's Caddy. It's only slightly larger and heavier than a small block Chevy, but it's got more cubic inches than even a big block Chevy and it's a close match, torque-wise to the Chevy big block. I've seen a few conversions into hotrods with that setup, and the results are very impressive. There's also a fair amount of aftermarket go-fast parts for the old Caddy engines, such as intakes, headers, roller rocker arms, etc. There used to be a pretty fair supply of those engines, but they're probably a little scarce these days.
Jerry
