you answered it yourself..the Napier THG does offer better oil control over the RBT , so if that’s the only difference, then the customer has the choice of maximum oil control by going with the THG second. Expense is usually the other factor..THG are usually more expensive

Hastings is the bottom of the barrel when it comes to rings by the way…they cater to the cheap low budget builder doing mostly stock type builds. they do offer their “tough guy” line for cheap **** who do performance builds.

you’ll notice once you get into low and ultra low ring sets, they will usually come with a Napier THG second, not the RBT. I’ve successfully run ultra low 3mm and 2mm oil rings on the street with a THG second with no problem. the engine may be down 1/2 a quart after season..which isn’t a problem

most bread and butter stock ring sets with standard tension oil rings, come with RBT seconds. These are $40.00 rings sets

 

If someone is stuck using old 5/64 5/64 3/16 piston rings lands.
at the minimum, you should be using medium tension oil , a reduced radial dimension Napier THG second with back spacer, and a top ductile iron reduced radial with back spacer.

your running hot problems must just go away

 

Bill
Some very good points. That is a good question just how much of the excessive cylinder wear was do to the cylinders being fuel washed.

 

So the main reason they can run a lower tension oil ring is because its low tension?

 

What brand and model of hone do they have?

 

No. Ask Dale why the 2 and 3mm oil rings don’t seem to drag as much, but still have good oil control, vs the conventional 3/16 stuff. Why?
He mentioned wanting to “grit your teeth” when you rotate an engine with the bigger oil rings.

 

Again you show that you really don’t know much about how the manufacturing world works.
First of all, Hastings sells rings to guess who? Total Seal and a host of other “manufacturers”. And guess what, Total Seal sells to Hastings and others as well. If someone makes a ring that’s needed by another company for some reason, they just buy it from them. And although I use mostly Mahle stuff, Hastings makes a pretty good steel and steel nitride top ring that works really well in power adder or race only applications.
Lastly, you actually just contradicted your own statement. “Ring pack” is just a grouping of rings for OEM or established aftermarket piston kits.
If the Napier second offers better oil control, which we both agree on, why wouldn’t they adjust the oil ring tension in those packs if, as you say, are made to work together? Simple, then they’d have another part number to inventory. So yes, the ring packs work together, but they’re not exclusive to the performance of each individual ring. It’s simply a good, better, best and really much more of a size grouping for the piston guys, whether it be for OEM, aftermarket, or custom. One or two of the rings in the pack may be better than another yes. But they’re there mostly to facilitate ease of application. If you want the best combination for every scenario, you can buy different individual rings as you eluded to.

 

You kinda touched on it, but missed the bigger issue regarding Carb vs EFI when it comes to fueling. Think about it.
And I have to disagree on the your take regarding thin ring break in, sorry. In my experience they actually break in quicker than a thicker ring. Because they conform to the wall better, contact area is maximized, and maximized more quickly.
A recent example, I dyno’d a Pontiac 455 for another builder recently. It had the 1/16, 1/16, 3/16 ring pack in it. We did about 6-8 pulls, and it made more power with each of those pulls before it finally leveled out, with no jetting or timing changes. Conversely, after the first pull or two, I don’t see that with the thinner ring packs. They seem to be more forgiving.

 

I did say they usually put the THG style second with low and ultra low oil rings. if you want to calm that adjusting the oil tension, that’s fine. it’s usually to reduce friction from the oil ring to start with
read it again.
I also use a lot of CP Carillo rings, their CPN and CPN2 style. with low and ultra low oil they only use THG seconds

 

Quote:
Originally Posted by Bernhard
So the main reason they can run a lower tension oil ring is because its low tension?
No. Ask Dale why the 2 and 3mm oil rings don’t seem to drag as much, but still have good oil control, vs the conventional 3/16 stuff. Why?
He mentioned wanting to “grit your teeth” when you rotate an engine with the bigger oil rings.Last edited by cutlassefi; Today at 04:20 AM.









Quote:
Originally Posted by cutlassefi
Any moly faced ring requires the wall to hold oil, regardless of ring thickness.
And your previous post lists a few good reasons for maintaining good oil control with a lighter oil ring. But you still haven’t hit on the single biggest reason. Think ring pressure.😎

Bernhard wrote:
So the main reason they can run a lower tension oil ring is because its low tension?

Mark please explain what you mean when you say ring pressure?

 

There are some on here that will say they knew this, but I’d bet money they didn’t.
i spent countless hours on the phone years ago with Mahles’ ring tech guy before he retired, talking piston AND ring development in recent years.
The explanation for this is really quite simple, and Joe P could probably shed more light on it.
A 3/16 oil ring has a rail that’s fairly thick, comparatively speaking. Conversely, a 2.00 or even 3.00mm oil ring has a substantially thinner rail. So, to maintain the same psi on the face, the part that actually contacts the cylinder wall, you need less overall pressure because it’s a thinner ring. The fact that the contact patch is less allows you to use less pressure to maintain the same psi on the face of the ring. The scraping you hear with a 3/16 oil ring is not only from the higher pressure needed to maintain the correct psi at contact, but also because the ring is fatter, producing more contact area as well. In addition any ring with less radial depth will mostly respond better because of its lighter weight/mass, which results in better control at the face and less flutter.
Finally, yes, modern EFI helps in ring life. But a huge part of that is cold start. How long is the choke in play on the avg carb? Probably at least a couple of minutes. Modern EFI is in cold start mode for as little as 30 seconds, maybe 45 at the most. Thats as big of an influence on oil life as anything.

 

a 3/16 oil ring can have the same tension as a 3mm or even a 2mm set. Total seal makes 3/16 sets with the same tension as the 2 &3mm sets for common bore sizes . They can also make a 3/16 any tension you want for any more size

the overall vertical dimension of the pack and or the vertical thickness of the rails, is not what controls the tension.

it’s the combination of the expander tab contact spot (where the inner part of the rail touches it) and it’s design , and the radial depth of the rails …is what controls the final tension …you never once mention the expander?

the expander contact spot can be adjusted (during manufacturing)to provide more or less tension on the rails..
you need to go back to oil ring school because you totally forgot how important the expander is. Here’s the critical tab that controls the tension of the rails.

 

How can someone who claims to be a know it all on oil rings, not even mention the expander ? Jeeesh

just sayin.

 

I’m well aware of what the expander does, but as usual you missed my point.
And yes you can get different expanders. That could influence the pressure the ring exerts on the wall. Duh.
And we all know, even if whatever I say is 100% what you believe, you’d still nit pick it. That’s common knowledge here btw.

 

you never even mentioned the expander in your explanation..duh. nitpicking the major part of the ring pack isn’t nit picking. it’s proving you’re a bs’r

those countless hours you spent on the phone with Mahles ring guy didn’t sink in.

 

I’m pretty sure anyone that’s been following this knows the expander is just that, it greatly influences the pressure of the oil rails against the wall.
How many times do you want to beat this dead horse?

 

no, not everyone knows the expander IS what dictates the tension. you also completely failed to mention that because you think you know what you’re talking about because you spent countless hours on the phone.

that must have been painful for him..probably pushed him into early retirement

 

Again keep beating this dead horse if it makes you feel better.
I know damn well what the expander does, and its relationship to rail thickness.
But as usual you had to try to one up me. Nice try.

 

Most shops do have profilometer, and for some time now.

 

Leaving Dale out of this, (sure he knows) how would this forum setup the rings on a 4.155 bore, from the top ring to the bottom oil rail. Conventional moly ring for street strip use, NA?

 

I'll bite. A safe/conservative combo is 1.5/1.5/3mm, second ring napier, standard tension oil ring. I'd probably consider 0.043 top and second these days, maybe try total seals gas ported ring package. The 2mm oil ring is intriguing, but I probably wouldn't have the courage to try, as I haven't had the time to play around with much engine stuff the last few years.

 

The long term oil control will be interesting with the 2mm oil rings on my 358, so far so good.