Head Gasket thickness and Hone Roughness

[KaminaSan]

Hey guys, so I have two overall questions:

NI bought a built short block because it was a good deal, and of course, I ended up running into some problems.

Number one: It had been bored/honed, to 86.5mm for Mahle PowerPak 8.5:1 pistons, and when I took it to my mechanics, they said that the hone job was pretty rough. When I asked what I could do, they said I should rehone it, but that might make the piston too loose in the cylinder, so I might have to resleeve/buy new oversized pistons.

How important is having a smoother hone? They said it would wear out quicker. but I don't have the money to buy sleeves/new pistons. What will be the downsides of the rougher hone?

Would I safely be able to bore out the stock block to 87mm and put 87mm pistons?

Question 2: My block had been decked twice, because the first time the guy I bought the block from didn't have it decked with the oil pump. The head I'm using has also been decked/resurfaced. How thick of a headgasket should I go with to maintain 8.5:1? I don't have the specs on exactly how much was taken off.

Would 1.8 be alright, or should I go with 1.5?

Any help is greatly appreciated =)

[KaminaSan]

Anyone? No thoughts?

[jr_ss]

There are two hones, a rough hone and a final hone. The final hone is what the rings will break into and seal. I highly doubt that a final hone will take off enough material to have those pistons too loose int he cylinders. Have it done and run the motor. They can also mic the cylinders and your pistons to see if it's too larger.

To get the correct thickness you need to know what your deck hieght is and how much the head has been shaved. Read the FSM and you can figure out both pretty easily taking measurements then proceding from there.