How bad did I #$&% my piston up?

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This should be a sticky. You didn't know something. You asked. You LISTENED. Way to go, dude. You're little motor is gonna come out great. Cause you are FAR from a dumbass. Kudos.
 
mopar410 said:
4.03x.0065=.026195 ring end gap
.0015-.0020 is the piston to wall gap.
Make sure you gap the top ring only to .026
edit:maybe find a new machinist or atleast one that deals with performance parts.
Your engine could have been destroyed.
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I could have very well misunderstood what he was saying too. I get confused with numbers flying around.
 
Sheeot. I been doin this thirty years. I still get kunfrooshed.
 
JohnnyRingo said:
I could have very well misunderstood what he was saying too. I get confused with numbers flying around.
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No harm no foul,glad we were able to catch it before something bad happened.just remember engine builders and machine shops arn't always the same thing and mopars are less known around some shops so check you instructions on all you parts and also ask alot of questions here.
 
This is why Hypers get a bad name, folks use a .015-.020 ring gap and the ring butts while running hard and takes the top off the piston. Then its all those hyper piston fault.

.030 gap I would feel better with. What if its 100 degrees outside and the coolant temp gets to 200 and you decide to nail the throttle, if any of those 8 top rings butt, its kaboom time..I got kb hypers and I have done that and all was fine..sadly I trusted my engine builder to build the short block so can't say what the gap is
 
This is good info. for me. I'm old school and have only run cast and forged before. I always assumed the hypers would run cast type gaps. Didn't consider the ring being high and needing to be bigger gaps without running boost or juice. At least now i know if i use hypers to really pay attention to the gaps, thanks guys.
 
Not all Hypers run those gaps. The Sealed Power for example, does not. It's all dependant on WHERE the top ring is and how much silicone is in the pistons. Silicone expands at a different rate as aluminum and will change all the clearance specs. The KBs have a higher percentage of silicone.
 
OldmanRick said:
This is just a reminder as you may already know this. You need to stagger the gaps also. This diagram may not be exact for your application, just a reference so you know what i'm talking about.
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thanks for this diagram i have set my rings a little diff but close to this with no problems but from now on i will follow this ....
 
Not to resurrect old threads...but am I missing something with the bottom piston ring end gap? KB's site talks about the top ring gap, but I can't find anything for the second ring. Is it the same specs as the top ring?

The build project took a backseat while I had other stuff going on, so I'm just now getting back at this.

Thanks guys.
 
First - the 2nd ring is not a compression ring. It's designed from the start to be an oil scraping ring. It does not hold pressure well as a result.
Now - There are two schools of thought on the 2nd ring & this will be a little odd simply because of the KY hyper special gap considerations:
One group like to use the same gap or smaller than the top ring. The 2nd ring does not get as hot because of it's placement and the oil that bathes it as it works. IMO - you can't go wrong that way. But, you may be giving up some power at higher rpms.
The second group, of which I am a member, is that the 2nd ring while not designed to hold pressure, does have some pressure built up between the first and 2nd rings in normal operation. When that pressure gets high enough, it can push the top ring up off the piston's ring land. When that happens, the top ring loses sealing ability and you get blowby and less power. A larger gap in the 2nd ring allows the top ring to do it's job better over a wider operating rpm. So the second group believes in running a larger ring gap on the 2nd ring. I use 25% as the multiplier. So an engine with a .016" top ring gap gets a .020" 2nd ring gap.
That being said - with KB's special top ring gap requirements - the 2nd ring should be gapped as if the top ring were gapped "normally". So where the "normal" top ring gap would be around .018, the 2nd ring gap should be around .023".
So if I were gapping your rings - the top would be .026", the 2nd would be .023.
 
moper said:
First - the 2nd ring is not a compression ring. It's designed from the start to be an oil scraping ring. It does not hold pressure well as a result.
Now - There are two schools of thought on the 2nd ring & this will be a little odd simply because of the KY hyper special gap considerations:
One group like to use the same gap or smaller than the top ring. The 2nd ring does not get as hot because of it's placement and the oil that bathes it as it works. IMO - you can't go wrong that way. But, you may be giving up some power at higher rpms.
The second group, of which I am a member, is that the 2nd ring while not designed to hold pressure, does have some pressure built up between the first and 2nd rings in normal operation. When that pressure gets high enough, it can push the top ring up off the piston's ring land. When that happens, the top ring loses sealing ability and you get blowby and less power. A larger gap in the 2nd ring allows the top ring to do it's job better over a wider operating rpm. So the second group believes in running a larger ring gap on the 2nd ring. I use 25% as the multiplier. So an engine with a .016" top ring gap gets a .020" 2nd ring gap.
That being said - with KB's special top ring gap requirements - the 2nd ring should be gapped as if the top ring were gapped "normally". So where the "normal" top ring gap would be around .018, the 2nd ring gap should be around .023".
So if I were gapping your rings - the top would be .026", the 2nd would be .023.
Click to expand...

Ok, thank you very much for the response. You stated though that the second gap should be 25% larger than the first ring, so if my gap on the first ring is .026, I got .032 for the second gap if I did my math right. Am I mixing something up with your estimation?

Thanks again.
 
Go back and re-read moper's post. He said that he recommends the 2nd ring gap be 25% larger than a stock top ring gap.
 
JohnnyRingo said:
. I can BARELY feel it if I run my finger nail along it, but can't feel it when I run the tip of my finger along it. How detrimental is that/how bad did I mess it up?

Kyle
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If you can't catch it with a fingernail, then it will be ok.

You may be able to use some emery cloth for crank polishing to knock it down a bit.
 
Stagger the rings like the guy said, doesnt matter where the gaps end up...as long as they aren't lined up with each other. FWIW...if a bore is well out of round...the gaps will find their way to lining up regardless. I would gap the rings at .026.. but that's me. Good luck.

As for the second ring, I leave them on the big side of stock recommendation, like .018
 
JohnnyRingo said:
This is why I admit to being a goon with this stuff and save myself from $3,000 of heart ache. Going back to that page for another read. Thank you, sometimes I just need to be smacked in the head like that.
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thats what i set mine at .26
 
I use 25% as the multiplier. So an engine with a .016" top ring gap gets a .020" 2nd ring gap.
So if I were gapping your rings - the top would be .026", the 2nd would be .023.[/QUOTE]

( the top would be .026", the 2nd would be .023.) This is what is confusing. I think moper meant .033. tmm
 
moper said:
First - the 2nd ring is not a compression ring. It's designed from the start to be an oil scraping ring. It does not hold pressure well as a result.
Now - There are two schools of thought on the 2nd ring & this will be a little odd simply because of the KY hyper special gap considerations:
One group like to use the same gap or smaller than the top ring. The 2nd ring does not get as hot because of it's placement and the oil that bathes it as it works. IMO - you can't go wrong that way. But, you may be giving up some power at higher rpms.
The second group, of which I am a member, is that the 2nd ring while not designed to hold pressure, does have some pressure built up between the first and 2nd rings in normal operation. When that pressure gets high enough, it can push the top ring up off the piston's ring land. When that happens, the top ring loses sealing ability and you get blowby and less power. A larger gap in the 2nd ring allows the top ring to do it's job better over a wider operating rpm. So the second group believes in running a larger ring gap on the 2nd ring. I use 25% as the multiplier. So an engine with a .016" top ring gap gets a .020" 2nd ring gap.
That being said - with KB's special top ring gap requirements - the 2nd ring should be gapped as if the top ring were gapped "normally". So where the "normal" top ring gap would be around .018, the 2nd ring gap should be around .023".
So if I were gapping your rings - the top would be .026", the 2nd would be .023.
Click to expand...
He went over the difference in a regular piston top ring and a KB top ring,looks like it was a little confussing for some.He states that the second ring should be gapped 25% at what stock type top ring would be not what a biggier gap KB top ring is.
 
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