Re: 428 Block ID?
Why don't you save yourself a lot of head aches and drop in a standard size 428
piston set in your 390 block with the original crank and rods. They fit. you then have to
have your rotating mass balanced. That combination will EAT any 428 out there. The stock 390 maximum r.p.m. based on piston speed is 5,556 r.p.m. The 428 maximum r.p.m. based on piston speed is 5,276. your 390 with the 428 piston combo will, with
very little add ons will get you just this side of 400 h.P. The stock 390 comes in at 389
H.P. They had to under rate the H.P. for nascar racing.