guys - pulled a 455 apart today. Pistons say “30” on top......assume that’s 30 thou over. That’s too bad as there is some heavy rust in a couple bores. What’s the max these 455 can be bored? Thanks At least I got a st of 1970 heads out of it, crank looks good.
Well, around 30 thou. Not what you wanted to hear I'm sure but even at 30 thou there could be overheating issues...
38 over is the norm,..TA has some 40 over pistons no issue with overheating with either. If it's just rust that's no problem it takes a good bit of corrosion to booger up a bore in a buick block,..they aren't like the chevy butter blocks
Yeah, if its .030" and you get .038" pistons, the machine shop can skip boring it and just hone the .008" out if they think that'll be enough to remove for a good clean up? Wouldn't hurt to ask. Sonic checking is always a good idea to do on a performance build as well to make sure there isn't any thin cylinder issues from core shift to deal with.