champLSinteg

I just got a set of 83mm CPs and I have heard that they had problems with the valve reliefs breaking off but they had been fixed. Do these look meaty enough or should I have my machinist shave them down?

Jared

depends on who is tuning the car, just like any other piston.....

champLSinteg

I realize it can all come down to tuning but from what I heard the valve reliefs would break very easily.

Cole D

pm Mike Laskey ( ninesecrx) he will let you know

HiProfile

Its usually the 81.5/81's that have the problems, since they never removed anything and its very thin (1mm thinner than yours). I don't think you'd have a problem, but if you think it could EVER run slightly lean, or you plan on 600+ whp, definately gouge those lips.

Some people will tell you it was ONLY an issue with bad tuning. I simply can't accept that the cars with the poorest tunes coincidently were running CP's. I haven't heard of those terrible tuners having that happen to all the other cars (with different pistons) they tried to destroy, I mean tune.

Whats better, running an inferior piston that can take some abuse, or a superior piston with a 'glass jaw'?

blackeg

i was making 400s with new cp's. my sleeves sank so the motor had something happen to it, the pistons are still fine