Thread: Piston ring question

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I'm starting to build my engine and already have a question. I was going to gap the rings but there isn't much direction and they came in a plain white box. They came with my Scat rotating assembly here:

http://www.jegs.com/i/Scat/942/1-92000BE/10002/-1

The pistons have directions for "KB Claimer tech tips". It gives me a ring end gap factor of 0.0065" for street normally aspirated, I figure this is what best describes mine (AFR heads, comp xe262 cam.....). So from this I get a ring gap of .0262 or .026 for my measurements. This is all I got, so do I do all the rings with that gap, I thought the 2nd ring was opened up a bit more??

Also the ring have 8 with the shiney sides and 8 just plain sides same color as the tops. I assume the shiney ones go on top then the dull ones next followed by the other set.

Thanks,
Sean

Hypers run hotter on the top ring, so need additional end gap to prevent butting. You are correct, 0.026"/0.027" on the top ring for a 4" bore. The second ring can be gapped conventionally at 0.0045" per inch of bore (0.018" for a 4" bore).

The first and second rings have a chamfer on the top inside corner. This chamfer on the top ring goes up when installing the rings. Upon combustion, the pressure comes down the side of the piston, then travels between the top of the ring and the top of the ring land, pressing the ring down on the bottom of the ring land to form a seal. It then travels to the back side of the ring to compress the ring out against the cylinder bore and contain combustion pressure. The chamfer on the ring edge allows the gas to make the turn from the top of the ring to the inside edge of the ring. The second ring is the scraper ring and the chamfer goes to the bottom of the ring.

Thanks Tech, I got your other reply. Seems like you're up late with me lately . I could use a hand.

Sean

Originally Posted by sgo70

Thanks Tech, I got your other reply. Seems like you're up late with me lately . I could use a hand.

Sean

I'm usually up until the wee hours, checkin' global stock markets and trying to formulate an investment plan for the next day on the NYSE and Nasdaq. It's been tough trying to make a dime all this year. The markets are nuts, you never know which way they will go on a given day. Everybody and his/her brother are in there trading on emotions. Not like it used to be.

Even your friendly Federal Government got in on the act, taking over Fannie and Freddie. I really feel sorry for anyone who was holding those stocks. If Bob and Betty Citizen were holding a large block of that stuff in their retirement portfolio, they got wiped out. I read where one hedge fund manager was holding 80 million shares.

Okay now I'm getting confused.

I got all the rings gapped and even phoned KB to make sure the shiney one was the top. Now I'm looking at the second ring and it has a chamfered inside corner and a dot on the opposite side . The directions say to install the dot towards the top of the piston but that will put the chamfer opposite what you said facing down????


What now? I've read it about ten times.

Sean

Sorry for the confusion Sean, I get confused in my old age. The bevel on the top ring goes up. On the second ring, it goes down. I really didn't mean to cause you any grief. I have corrected my post above.

No problem, I searched around and found a post that had the exact same rings as me having the same problems. Regardless you've been a big help.

Sean

just remember all dots or letters like T go up and if no marks and no bevel then that will be your top ring a shinny ring could be moly filled is the top most all the time the darker ring plane iron is the 2 ring