You should be able to swap cranks however, for smooth running and long life, the rotating assembly (everything that is attached to the crank and spins) should all be balanced so, you would want to have it balanced and not just swap the parts. If they are the same bore, you can probably swap the whole rotating assy from the old to the new block (checking clearances etc)

Lots of 350 swaps done.


Mike
1955 Chevy 6400 ex-flatbed (no bed now!) sold September 2023
In the Stovebolt Gallery
1958 Chevy 6400 flatbed W/dump
In the Stovebolt Gallery
1959 Chevy Suburban Owned for almost 20 years, Daily Driver -- sold May 2016
In the Stovebolt Gallery

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