OK, well that didn't really come out right, 4.25" is not a small bore. Mopar did have some comparatively large bores - 400 is 4.342" which is big, maybe that was my logic for saying the 383 bore was small? I dunno. Funny too because I'm actually building the 438" stroker below with my friend based on a .060" over 383 block. Bore is 4.310" so getting into 400 territory.
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My point is the 383 is sorta equivalent to the 318 in status. There are millions of them out there but no one really wants 'em because the 400 makes a better combo, all things being equal. It's the same logic as the 318 vs. 360 argument - the blocks have the same external dimensions but the one with the bigger bore will generally make more power in an average build.
