Reply To: Re: .060 Cylinder Overbore Question

[62oldsf85]

Bruce,
I did a .030 overbore on mine. One of my cylinders was shot from a spun rod and piston shattering that got thrown through the block (no kidding). To prepare for sleeving that cylinder, we actually bored out .100 to remove the original cast sleeve. It looked like peeling a thick tin can. A .010 clean up can sometimes get rid of the rim ridge, but you would use a ridge reamer to do that and then look at the condition of the cylinder (the circumference of the ridge is actually smaller than the cylinder, so once you use the ridge reamer, you’re usually good up on top, it’s the middle and the bottom of the cylinder, the scoring in it, and the actual true roundness of it that they’ll measure to determine whether or not they need to take more out.

Anyway, my experience with those cast sleeves is that they are pretty damn thick, and it takes a while to get to the water jacket. This engine does produce a lot of heat, but if your block’s water passages are cleaned well and your cooling system runs effectively, I think you could do a .060 over. I had my piston tops jet hot coated for heat resistance, you might consider that. It was pretty cheap (about $200 for all 8) and who knows, but I figured that was cheap insurance.