Piston ring problem

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DieWilde13

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Hi Guys, maybe you can help me with a problem that i ran in.
I rebuild a 383 and want to use new piston rings. I ordered a set from Sealed Power. E233K
I figured that the top ring is a lot narrower than the second one. second was normal with 0.196, but top ring is only 0.15, so i would have 0.90 back clearance behind the ring. Way too much!
Ok, so i thought i just order another one of them, maybe its packed wrong or whatever.
Guess what, second set is exactly the same.
So i was going to check another manufacturer and ordered a set from Hastings, 2M683. And what did i see..... also these top rings are that narrow.
Did i miss something? Was there a change in design? I dont want to use them, has anybody an answer for that?

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What do you mean? The Pistons are Stock Pistons. 5/64 5/63 3/16
Normal Ring wide is around .197 . The Ring groove is .245 deep.
Second Ring of the new sets are .197.
Just the top ring is only .150 wide or deep or how its descriped :)
 
What do you mean? The Pistons are Stock Pistons. 5/64 5/63 3/16
Normal Ring wide is around .197 . The Ring groove is .245 deep.
Second Ring of the new sets are .197.
Just the top ring is only .150 wide or deep or how its descriped :)
Are both the 1st and 2nd grooves the same depth?

A little ring tech the second ring should have a taper face, it is used for oil control" it lifts the oil off the wall and feeds it to the oil control ring to feed to the inside of piston for return to the pan.


The top ring is the compression ring to stop the combustion from leaking past, it sounds as if the ring folks are using a lot of back clearance for loading the ring out to the cyl walls with a bunch of pressure. What surface coating is on the top ring? Chrome or moly filled.

One thing most people don't understand about rings are each ones function there ius a lot of myth about them especially oil control. There is always some compression leakage past the the top ring which is used to pressure force the oil off the wall along with the second scrapper ring to force it through the oil ring to the inside of the piston. There have been occasions where the ring seal from board finish has been so good that oil control was bad as there was no blowby to force the oil back inside piston. Been there done that.
 
Yes, the grooves are same depth.
'I hav a old set of 233K rings laying around for lots of years, and in that set the rings are how expected the same size 1st and 2nd
 
The stock type ring sets “should” adhere to the “D wall” radial thickness dimension, which is: bore divided by 22.
4.250/22=.193.

I don’t know if it would get you anywhere, but it might be worth emailing Hastings and asking them why the rings you bought don’t have that spec top ring in the set.
 
The stock type ring sets “should” adhere to the “D wall” radial thickness dimension, which is: bore divided by 22.
4.250/22=.193.

I don’t know if it would get you anywhere, but it might be worth emailing Hastings and asking them why the rings you bought don’t have that spec top ring in the set.
There has been a move a while back to reduce the radial tension on the top ring to reduce friction and bore wear. We saw this a lot in the ring packages we were getting from the piston suppliers and also ring suppliers when I worked at Hasselgren Racing engines. Especially noticeable for the chevy LS engines we were doing for Grand Am GTP cars.

Just for kicks take a top ring from your older set squeeze it together and then do with one of the top rings of new set and see the difference.
 
If the ring is .15, you sure you’re not building a tank engine?

Did you measure the ring glans and the thickness of said glans?

Also post up a pic of the piston.
LOL, Freudian slip perhaps. I haven't measured the thickness of my glans but it's nothing awe inspiring.
 
I already contacted Sealed power and Hastings, but i get no answer from both........
I went through the same thing last year on a .070" over 383 build for my budget bracket car. It took about 2 months before I finally got a knowledgeable guy from Sealed Power's tech that said the top ring is .145" radial wall steel. I spoke with a few other machine shops and they said they were concerned as well but they work fine. I had ordered the Hastings and then the Sealed Power and they are all Hastings rings except the Sealed Power set had end gaps in the low 30s, the Hastings were about .019" so I sent the SP rings back. The ring set for my NHRA stocker 426 has 5/64ths ring grooves .200" deep in the CP pistons as required but with side spacers and none behind the ring I'm running a 1.2mm steel top and napier iron second ring both with .150" radial wall so as long as you have an end gap under .025" or so you'll be fine.
 
That is very interesting. Thank you! So you think i should give it a try....ok
Yes, as long as the end gap is within reason you should be fine, the new style top ring is supposed to live longer as it is harder and has less tension but it needs a round cylinder that has been honed properly and don't overload the cylinders with heavy oil upon assembly, if you're not sure transmission fluid will work fine with a small amount of non detergent light oil on the piston skirts. I may be visiting some family later this year in Germany not far from where you are, small world, ha.
 
That is very interesting. Thank you! So you think i should give it a try....ok
That goes along with my post above. I spent 24yrs building race engines initially for formula Atlantic using the Toyota 4age engine we were getting 250hp from a 1600cc 4cyl and turning them 9500 to 10,000 we were using Mahle pistons and rings the top had very little wall tension it used compression blow by to pressure force the ring to the wall to seal.

Something most don't know is wide high tension rings will skid and chatter on the wall if to much mechanical pressure, working with the Allison's with the 6" stroke was horrible for that problem they used 1/8" wide rings so Allison solved the problem by making the top ring rounded chrome faced and tapered top groove.
 
Yes, as long as the end gap is within reason you should be fine, the new style top ring is supposed to live longer as it is harder and has less tension but it needs a round cylinder that has been honed properly and don't overload the cylinders with heavy oil upon assembly, if you're not sure transmission fluid will work fine with a small amount of non detergent light oil on the piston skirts. I may be visiting some family later this year in Germany not far from where you are, small world, ha.
Back when I worked at the race engine shop we came up with a method to hot hone the blocks through and with the torque plates by circulating hot oil through the block at 190F temp. You can't quess how much a cast iron block changes cold to hot, by doing it this way guaranties the cylinders are straight and round within 1/2 thou when hot running. amazing the diff in power that way.
 
Back when I worked at the race engine shop we came up with a method to hot hone the blocks through and with the torque plates by circulating hot oil through the block at 190F temp. You can't quess how much a cast iron block changes cold to hot, by doing it this way guaranties the cylinders are straight and round within 1/2 thou when hot running. amazing the diff in power that way.

No one in drag racing does hot honing any more. Not sure what the asscar guys do.
 
No one in drag racing does hot honing any more. Not sure what the asscar guys do.
Having spent a lot of time drag racing sort of back in the dark ages late 60's early 70's with the small amount of time "passes" we would get from a fresh hone ring job I was using the TRW pistons with the "L" shaped factory supplied rings. So I expect it probably isn't worth the trouble when the leak down gets high after 10-12 passes, just to much work to soon?
 
Having spent a lot of time drag racing sort of back in the dark ages late 60's early 70's with the small amount of time "passes" we would get from a fresh hone ring job I was using the TRW pistons with the "L" shaped factory supplied rings. So I expect it probably isn't worth the trouble when the leak down gets high after 10-12 passes, just to much work to soon?

Nobody runs an engine at 190 any more.
 
Ok thats all interesting. I ordered a set from Mahle now and if these are also the same, i will build them in.
Maybe i need to check for some Spacer rings
 
It’ll be interesting to see what you get from Mahle.

Between Sealed Power, Hastings, and Mahle……..Mahle would be the one I’d most expect to use the narrower top ring.
I’d have thought the Hastings to be the most likely to still have the D wall spec top ring.
 
It’ll be interesting to see what you get from Mahle.

Between Sealed Power, Hastings, and Mahle……..Mahle would be the one I’d most expect to use the narrower top ring.
I’d have thought the Hastings to be the most likely to still have the D wall spec top ring.
They all come from Hastings is what I was told by a Mahle dealer, the moly top with .196"ish radial wall was phased out, if you get a set with it, it's old stock. Keith Jones at Total Seal said something similar.
 
Want to clear things up, the Mahle set is just normal as expected. Maybe an old set, but here are the rings .196ish, and i'm happy now.
But anyway, its interesting how things develop....
 

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