Looking for opinions on piston ring gap

MalcolmV8

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It happens man, we learn and move forward, don't feel bad. I asked a lot of people and looked around a bunch prior to putting them in. Not a lot of info was out there and had I been smart and googled "gapless ring problems" I would have been enlightened right away. Total Seal sales people on the phone totally sold me on the product and were very convincing.
 

SlowSVT

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This sounds more like a problem with the oil rings not seating properly which is usually results of a hone that was too smooth not allowing the rings to seat. I had this problem with a big bore motorcycle jug I got from Powerall. On start-up it blew soo much oil I had to break the motor down again and ran a flex-O hone down the bore. Restarted the engine and the problem was immediately solved. The claim by Total Seal about the gargantuan leaps in cylinder sealing seem a bit overstated. Even with conventional rings the gap is very tiny and won't contribute to huge blow-by losses. Plus this is a blown engine which will see pressure as well as vacuum I don't know where they are coming from regarding the integrity of the valve stem seals. The gapless ring should be moved to the second ring in a blown engine which won't have the mechanical integrity of the heat transfer efficiency of a single ring plus it will prevent the lower rings from seeing gas pressure needed to drive the rings down onto their lands and out against the cylinder wall.

Nothing worse then having to break down a brand new engine to correct a problem. Just because a shop tell you the used a hone stone that was XXX grit doesn't mean the actual hone was equivalent of the finer grit due to clogging of the abrasive. That is where your problem likely originated from.
 

MalcolmV8

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This sounds more like a problem with the oil rings not seating properly which is usually results of a hone that was too smooth not allowing the rings to seat. I had this problem with a big bore motorcycle jug I got from Powerall. On start-up it blew soo much oil I had to break the motor down again and ran a flex-O hone down the bore. Restarted the engine and the problem was immediately solved. The claim by Total Seal about the gargantuan leaps in cylinder sealing seem a bit overstated. Even with conventional rings the gap is very tiny and won't contribute to huge blow-by losses. Plus this is a blown engine which will see pressure as well as vacuum I don't know where they are coming from regarding the integrity of the valve stem seals. The gapless ring should be moved to the second ring in a blown engine which won't have the mechanical integrity of the heat transfer efficiency of a single ring plus it will prevent the lower rings from seeing gas pressure needed to drive the rings down onto their lands and out against the cylinder wall.

Nothing worse then having to break down a brand new engine to correct a problem. Just because a shop tell you the used a hone stone that was XXX grit doesn't mean the actual hone was equivalent of the finer grit due to clogging of the abrasive. That is where your problem likely originated from.

Russ the car didn't blow smoke and still doesn't. If you watch the exhaust carefully on warm you see what appear to be wisps of steam but is actually smoke as it warms up. Very tricky. From my searching other gapless ring uses also note no smoking on the exhaust. Yet the exhaust, piston tops etc. are caked with black sooty burnt oil. I'm assuming it's the way it's getting by the rings it's not smoking? little bit at a time but consistently. I really don't know.

I find way to many people having oil consumption issues with gapless rings who then go back to conventional and all issues are fixed to believe it's a honing issue.
Dave (Juiced46) got back to me and said his motor was torn down and re-ringed 4 times in 2 months trying to solve the gapless ring oil burning fiasco and finally on the 5th time he went back to conventional gapped rings and everything was fixed.

The valve stem seals they are saying will leak in vacuum conditions such as idle if they're pretty loose or deceleration when your vacuum is at its peak.
 

01yellercobra

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Are you thinking about tearing down the engine again? I still have the big bore in the garage for future use. I'm thinking it's going to get a set of conventional rings next time around.
 

MalcolmV8

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Yes I need to hone the block and re ring the pistons with conventional rings. Burning a quart of oil every 200 miles is worthless.
 

Weather Man

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Wowser, you aren't kidding about the welter of confusing information on gapless rings. What is obvious to me though is that asking a vendor about them is a mistake.
 

SlowSVT

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Russ the car didn't blow smoke and still doesn't. If you watch the exhaust carefully on warm you see what appear to be wisps of steam but is actually smoke as it warms up. Very tricky. From my searching other gapless ring uses also note no smoking on the exhaust. Yet the exhaust, piston tops etc. are caked with black sooty burnt oil. I'm assuming it's the way it's getting by the rings it's not smoking? little bit at a time but consistently. I really don't know.

I find way to many people having oil consumption issues with gapless rings who then go back to conventional and all issues are fixed to believe it's a honing issue.
Dave (Juiced46) got back to me and said his motor was torn down and re-ringed 4 times in 2 months trying to solve the gapless ring oil burning fiasco and finally on the 5th time he went back to conventional gapped rings and everything was fixed.

The valve stem seals they are saying will leak in vacuum conditions such as idle if they're pretty loose or deceleration when your vacuum is at its peak.

Malcolm, I responded to your post but the site locked-up on me again and I lost the post.

I'm having a hard time believing all that oil consumption is due to a gapless compression ring with a conventional ring in the middle. The are 2 oil control rings with are there for that very purpose and it appears they are not doing their job. Total Seal has been making gapless rings for decades if they have such a high failure rate they would have stopped making them years ago. Your problem does not even appear to be the gapless ring related but an oil control issue I would be looking very hard at the hone. Just about every oil control problem I've seen on brand new engines stems from too fine a honing finish that won't abrade the ring surface allowing them to seat to one another. Imagine polishing the cylinders on a brand new engine it will blow oil like there is no tomorrow the rings will never seat.

The valve stem oil blow-by claim is completely bogus. Imagine the vacuum being pulled when you let off the gas at high rpm's compared to idle. Did you use Teflon seals?
 

MalcolmV8

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Malcolm, I responded to your post but the site locked-up on me again and I lost the post.

I'm having a hard time believing all that oil consumption is due to a gapless compression ring with a conventional ring in the middle. The are 2 oil control rings with are there for that very purpose and it appears they are not doing their job. Total Seal has been making gapless rings for decades if they have such a high failure rate they would have stopped making them years ago. Your problem does not even appear to be the gapless ring related but an oil control issue I would be looking very hard at the hone. Just about every oil control problem I've seen on brand new engines stems from too fine a honing finish that won't abrade the ring surface allowing them to seat to one another. Imagine polishing the cylinders on a brand new engine it will blow oil like there is no tomorrow the rings will never seat.

The valve stem oil blow-by claim is completely bogus. Imagine the vacuum being pulled when you let off the gas at high rpm's compared to idle. Did you use Teflon seals?

It's very hard for me to know for sure. Same shop machined and honed my block as before and he's done many others for me and been in business many years doing hundreds, probably thousands of others. Not to say mistakes don't happen but if my hone wasn't good and the rings didn't seat why did the top gapless ring seat so well? It has 0% leak down. I've never seen a ring seal so well in all my life.

I'm certainly not a ring expert which is why I've spent literally hours and hours reading articles, threads and other info I can find online trying to understand and educate myself in the process. I've found more than one article that explains how the 2nd ring's function is 85 to 90% oil control. This leads me to believe it's an important part of oil control and that the oil rings themselves cannot alone handle it.

Interestingly enough in the process of searching I found some articles referencing a production issue Chevy had at one time with their LS engines consuming oil. They changed the 2nd ring to a Napier design and it cured it. That right there tells me the oil control rings alone cannot cope with all the oil. Obviously they play an important roll but are not the soul source of oil control.

The valve stem thing is what Total Seal says. I agree deceleration from high RPMs will pull a very high vacuum. They say even higher with a gapless ring. Who knows. As for my seals, originally I had what ever the shop doing the head work put in there. Second time around I put in Felpros. No change in oil consumption.

I went ahead and ordered a new set of rings. The exact same thing I ordered when originally spec'ing out this motor actually before Total Seal convinced me to convert them to gapless. We'll see how it goes non gapless this time.

BTW didn't we cover the copy / paste thing prior to posting lol :) this site locks up a lot on posting, it's a good save.
 

MalcolmV8

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Thought I'd post an update for others researching the topic. I tore my motor down to a bare block, had it honed and put conventional piston rings in. Put the car all back together. My brand new exhaust system was coated in a black nasty soot from all the oil burning. I installed new mufflers this time around (for sound) but it gave me new piece of exhaust to keep an eye on.

I re-installed the same black sooty O2 sensors as there's no point in ruining the brand new set if that didn't fix the issue. Put a few hundred miles on the new setup and pulled the mufflers to check. Nice light grey inside of them. No black soot. Pulled plugs and they're staying clean and look a million times better than the plugs that were in the oil burner setup. I also pulled an O2 sensor and it actually burned all that nasty black soot off of it and it's a nice light grey color. This is great news.

So for me personally ditching those gapless rings and going back to conventional cured that horrible oil consumption issue. Of course now I no longer have that perfect sealing top ring so I get blow by and a bit of an oily mess out the valve covers, especially the passenger's side, so I'll need to install some catch cans. I'll gladly take that over burning a quart of oil every 200 ~ 250 miles.

Based on my experience I couldn't recommend gapless rings to anyone.
 
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01yellercobra

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After this thread I've decided I'm going to stick with conventional rings for my next build.

Did you go with moly or stainless upper rings?
 

01yellercobra

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Stainless upper and iron second. Hard lesson learned but now I know lol.

Ok. I was thinking of going back to moly when I build my engine again. But I guess we'll see what I decide on for a power level when the time comes.
 

MalcolmV8

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Ok. I was thinking of going back to moly when I build my engine again. But I guess we'll see what I decide on for a power level when the time comes.

Do some reading up on that and even call a ring company like Total Seal and see what they tell you before you do that. In summary moly is no good for high power and boost.
 

SlipperySnake

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I’m having these same issues and have a gap less top but I have a Napier 2nd which from the GM research you said fixed the oil control issue. I’d be curious of your thoughts on this. Smokes like a train at idle. Under throttle it’s no issues. Literally all the same issues.
 

01yellercobra

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I’m having these same issues and have a gap less top but I have a Napier 2nd which from the GM research you said fixed the oil control issue. I’d be curious of your thoughts on this. Smokes like a train at idle. Under throttle it’s no issues. Literally all the same issues.
He ended up going to standard style rings. I won't run the gapless rings in a mod motor again.
 

MalcolmV8

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I’m having these same issues and have a gap less top but I have a Napier 2nd which from the GM research you said fixed the oil control issue. I’d be curious of your thoughts on this. Smokes like a train at idle. Under throttle it’s no issues. Literally all the same issues.

He ended up going to standard style rings. I won't run the gapless rings in a mod motor again.

Yup threw those gapless rings in the trash and never looked back. After all the tear downs, rebuilds and attempts at making them work I'll never touch a set of gapless rings again.
 

01yellercobra

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Yup threw those gapless rings in the trash and never looked back. After all the tear downs, rebuilds and attempts at making them work I'll never touch a set of gapless rings again.
Sorry if I stepped on your toes here. I wasn't sure if you were still coming around.
 

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