six pack intake question
There are two "series" of big block, "B" & "RB".
B engine are the ones with 3.375" stroke: 361, 383, 400
RB engines are the ones with 3.75" stroke: 413, 426 Wedge, 440
The RB engines are a bit taller and have a slightly wider intake manifolds (about 1") than the B engines.