New 440 Source 4.500" Bore RB Block

4.56 is typically the comfortable maximum bore size for a KB based block, so 605 cubic with the 7/8 stroker and a set of well worked B1 or Indy heads could make some huge output with a “close to shelf piston design.” But, at that point, you’ll start pushing the envelope or reliability that can be expected with the paired center exhaust valves. Hence the need the need for the Hemi version…