First off I want to thank all you guys who have helped me out in the past. I find this forum has lots of knowledgeable members.

I'm overhauling a Salvage yard 2008 6.0L LY6 engine.

So My cheap repair manual doesn't give ring gap specs. I found some information online and I'm not sure if it's correct or what gap to use in the wide range that I got from the information.

I bought total seal rings and Kieth Black Silv-o-lite 4.030" pistons. The piston instructions state that the top compression ring needs to be gapped 40% larger than factory specs and the Second compression ring and oil rings get set to factory specs. I read somewhere that the top of KB pistons break off only if the rings are not properly gapped. Makes sense if the rings get hot and touch each other then lock to the bore and break the piston. I also read that it's because KB places the top ring higher. The picture shows my stock piston has a higher top ring land than the KB piston. So why does KB want a 40% larger ring end gap? Should I use the smallest gap in the factory specs?

1st compression ring .008- .016" KB top ring .0112- .0224"

2nd compression ring .015-.027"

oil rings .009-.031"


On the left is the KB piston. On the right is the factory piston.



This is the factory piston before a bath in Berryman's Chem dip. That stuff is amazing!

 

I'm amazed at how clean that piston is... and how little wear is on the skirt. Are you sure that motor needed to be bored? Crazy.

Ring gap depends on your intended use. NA can be tighter than nitrous or Boost.

 

Likely no, but if you do, minimal is usually best. The cylinders are usually a little out of round as well.

Usually the smallest cast replacement is .020 over.

 

Cylinder #6 had the most wear. It had a noticeable ridge at TDC and a bit of wear at the BDC. I think the wear was from plugged oil rings and I bet that rock hard crud stuck on the pistons wore on the cylinders and shielded the pistons. I have never been so impressed with crud cleaner before. Berrymans chem dip is a must. Walmart had the cheapest price. I'm using it to clean my valves and connecting rods also.

This engine is going in my truck that will be a natural aspirated engine with a mild cam for added torque for my camping trips.

 

A freshly bored seasoned block is a keeper