I ordered standard size KB 167 pistons to use in my 318 that I am building for general street use. I had originally planned on reusing the stock pistons and so my block had previousely been checked out based on that. I have measured the piston to wall clearance for the KB's and I came up with one cylinder with a clearance of .0036 and then the other seven very close to .003 . The instructions that came with the pistons recommend the clearances at .0015 to .002 for my application. I am wondering if I can safely go ahead and use them or if I should return them and go a different rout?

 

Tough call, many questions before answering. What is your cylinder finish/preparation, honed? how much did you pay for them, send back/sell? Will it have headers and louder than stock exhaust to cover piston slap?

If they weren't too expensive and you just want to slap together an engine on the cheap sure go ahead.

 

My block was checked out by a recommended machinist and honed and prepped for the original pistons to be used. The KB's are brand new and could be returned with no problem. If I did that I would exchange them for .010 oversize and take the block back to get it matched to them. I just thought if I could run these without any problem it would save me the time and money to get more work done on my block. At this point I havnt decided if I will go headers or just a good duel exhaust system