Need to buy custom pistons and overbore for cyl damage from oil starve. How big can the machinist go on a 455 '72? I'm at .040" now. A little pre-info may prove beneficial. Thank you, guys.
I've heard you can go as much as .060, but you should have the machine shop sonic-test the cylinder walls to make sure there is enough there to do it safely.
There is a recent post on this. I think the thinking is to get a new block rather than go past 40 to 60. There are all kinds of reports once you go there of overheating and loss of the necessary minimum structural rigidity of the block. The blocks are plentiful still and you can save by being able to go with a standard size piston set.
