well there was some surface rust on the inside of the cylinder walls. and i brought it to be honed to fix that. they said that in order for the block to function, i need to have it bored, becuz the rust in two cylinder walls went a little too deep. what size would it need to be bored to for these pistons to work? i'll call them tomorrow and check to see what they did exactly. i might have the paperwork. this engine is one of my last projects ahead of me so i havent been paying too much attention to it unfortunately. so excuse my ignorance.