cdrod

I think I screwed up on the piston sidewall clearance for my engine. I misread the ICON piston chart (see attached) and told the machinist to set the clearance at .0040"; which is right in the middle of the spec for bores up to 4". The problem is my bore is 4.125" and the ICON chart specs .0045-.0055" clearance for bores over 4.1". I'm right on the transition (.025" over). Will this be OK or do I need to hone the cylinders for .0045" minimum clearance? The engine is 375cid, 10.3:1 static compression, around 8.8 dynamic compression, and I plan to run premium pump gas.

cutlassefi

I have to ask the obvious, why didn't you just give that sheet to your machinist to begin with?
I'd shoot for .005. They'll rattle a little when cold but they're designed for that.

cdrod

I did give him the sheet, we both misread it. So I should have him open them up a little?

cutlassefi

Yes.