I know some, but I have never claimed to be an expert. You are correct that some 425's had a different lifter bank angle, not really a problem if you know it up front as there are cams made for that angle. The 425's had steel cranks and were notorious for being quick reving BB's (sound familiar to all of your owning 427's!) The big bonus for the 455 is the extra cubes and that most everything in the aftermarket (There are some things out there
) is geared to the big block (but everything that fits on the 455 will fit the 425 as well). However, it was correctly stated that you need to talk with Dave and Casey. Anyone who can make a Pure Stock small block run in the 12's has some good ideas. I am planning on being at SCR8, so if you need to have a ride in a slow boat, let me know!
