AJ's Opinion; what size SBM do I need

.
Just the point I'd like to make about the bore of the 383 being so small. It's 4 and 1/4 in as in 4.250 which is the same as a 396 Chevy and a 426 wedge or 426 Hemi. I don't see where 4 and 1/4 in is a small-bore

The 396 is 4.094. Weird, but that's what it is. But I agree. I don't see anything with a bore 4" and over being as "small".