The factory built crankshafts  Stock strokes offered by
Chevrolet go like this. The 265 and 283 carry 3-inch strokes,
both with the smaller diameter journals. The 327 has a stroke of
3.25 inches and is available in both small- and large-journal
versions. The 302 crank goes goes back to the 3-inch stroke, but
unlike the 265 and 283 crank, the 302 spins on large-diameter
journals. The exception to this is the 1967 302 which had the
small diameter journals. The 350 crank has a stroke of 3.484
inches - also with large diameter main and rod journals. The
3.750-inch stroke 400-inch crank is unlike any of the other
cranks listed for the small block, it's cast, while many other
cranks are forged. Rod journals are common with those of the
late 327, 350 and 302, but 400's main journals are a one-off
size for the small block at 2.65 inches. The bore of the
400-incher is 4.125 inches. One of the most popular of all
combinations used to be the 327-crank-in-the-283-block trick.
This can be done without machine work, but yo