So I just recently bought a 408 short block from a company with diamond pistons, arp rods, and an eagle crank. I was sent 16 chromoly wrings that I thought were only for the second groove. I also received 8 black rings that are only about 1/4 of the thickness of the chromoly ones are, and i thought those were to go on the primary groove on the piston. The rest is normal, 8 oil rings, and 8 rings that go just above the oil ring and vise versa. The gaps r way off too so what should they be gapped at, if im running max and rarely 18psi of boost. Thanks.

 

It sounds like you may have a zero gap ring set. They use 2 rings on the compression ring, one thick and one thin. with gaps offset. Just a hunch. Call the engine parts supplier though.

 

ok, do u know what the compression ring gaps should be set at, because the black, thin ring is a huge gap. Also with the black ring, it is sort of sucked in with no tension, meaning there is a negative gap. Is that normal. Thanks again.

 

I've never used a set of zero gap rings so I can't give you much info in detail. I just had a hunch from what you said. If you want a ball park # on your application for FI I'd say .022-.028" gap on the top ring and ~.005" less on the second.
I do know that with zero gap rings you stagger the gap on each other so you have "zero gap" on that ring. zero gap is typically on the second ring though. The rings should have come with instructions, how about reading them.

 

I did read them. I just was hoping that someone would say something like .12" is ok for the top black ring. Because thats how it came and I think I have to get new ones now which I can't order until tuesday. ****. I was just hoping to try to get this built this weekend. Thanks for you help.