ok, I know this is a dumb question to ask, I shouldn't even be considering it, but I'm on a very tight budget. I have a 89 350 short block I'm rebuilding for my 90 formula. While removing the old piston ring, I damaged one piston. The edge is badley scarred and must be replaced. A oem piston, the same that is in it now is cheap, so I'm gonna buy it, is this going to have any negative effect on the way the motor runs, having one new piston. Weve done it at work before, but that was on very low mileage motors. Also how much do you think a machine shop will charge to press just one piston? and should I replaced the wrist pin as well?

 

If it is just the piston that was damaged and not the cylinder or rod, the only issue would be verifying the piston weighs the same as the rest.

Pistons typically come with the wrist pin. A shop shouldn't squawk about pressing just one piston. Probably charge you around $20. Maybe less, shouldn't be much more.

 

yea, it was just the piston that was damaged, it was messed up because the guy I bought the motor from was storing it all dissasembled, and this one was left in a tad bit of water, that corroded the piston ring, rusting to the piston. Then When I removed the ring, it damged the piston even more.

 

shouldn't be an issue, I replaced one in my 305 I got cheep. he'd blown a hole in the piston several thousand miles after a rebore. I honed the cylinder and put the new piston and ring in with the old ones, still running fine