Hey guys I recently rebuilt my engine and the machine shop bored it .030 over. Long story short I had an injector problem which ended up wearing down number 6 piston and now I have piston slap. I notice the cylinder walls are a little scored. Am I able to hone and use the same size piston in the cylinder? It has less than 1000 miles on the rebuild so I didn’t run it for very long.

 

You're going to have to hone it smooth, then check piston fit using a piston from another cylinder and a feeler gauge. The oldtime method was to use ring expanders behind the oil rings and oversized compression rings and filing the end gaps to the proper clearance. IDK why shops go .030 over when .010 would clean it up because now I doubt if you can find a .040 piston. Engine run fine with one piston oversized from the others. I have personal knowledge of a 50 Pontiac straight 8 with one cylinder .030 and the rest standard. It doesn't seem to make a difference in the way it runs.

 

You can also have that cylinder sleeved.

 

okay I bought a bore measuring gauge so I’ll gone and hope I can use the same size piston. Luckily I didn’t drive very long and the piston is the softer metal.