If it's just a general tranny question, yes, probably better in that section. I would think a regular 454 block is a bit less than a 396, only because there are likely a lot less 396 blocks around. I hear guys here saying 454's are hard to find now, but I see a lot for sale around me (upstate ny) for a pretty good price. I have had two in the garage for a couple years now, and just picked up another one last weekend. Look for something out of a p/u or suburban, or maybe a motorhome...lots of them used 454's. And if you're going to have to rebuild it anyway, as Gary said, go for a 496...a stroker crank and rods are only a tad more than the stock size stuff, and it's a lot more fun when it's done!!
