Bored 428- Is 60 over too much?

[mrtleavitt]

I have a 428 that I'm fixin to rebuild. From my sources I beleive it's from a '65 Thunderbird. Anyways, after looking into it a little more my brother found a "60" stamped on the pistons and we're guessing that means its bored 60 over. We think that's an awful big bore and that we'd run into trouble, what do you guys think? Is 60 too big? If not what is too big?

[Redcap]

Depends on how the block sonic checks.

[My427stang]

The answer is that if not run that hard, its probably OK if you are considering just a re-ring. It ran before I assume.

However if there is any bore taper and you need to bore more, that block is probably done.

Like the last post said, a good hot tanking and a sonic map for 150 bucks or so is very good insurance that you don't split a cylinder.

You can also have a machine shop do a partial block fill and stabilize the cylinders a little, its not expensive.

[averagef250]

You can dry sleeve it as well, but for a 428 block you can likely find another good one for less than sleeving.

[flatblack]

sleave it, sleaves only cost about 200 for a set of 8, thats the route i would go

[Tim P.]

as a rule a 0.60 428 is risky most never take them over 0.30 as there casted pretty thin to start with jmho.

[DuckRyder]

I'm with 427stang on this one.

I probably wouldn't bore one .60 over, but If I wasn't planning on pounding on it daily (heavy towing, high RPM, racing) I wouldn't have any problem putting one back together with a re-ring if it checked out.

A sonic check is a very good idea. It is possible that it is perfectly O.K., just depends on the core shift it the specific block.