3MM OIL RING TENSION

[joespanova]

So...........here I am for the "umpteenth" engine freshen and this time , since I'm going to a 377 and want the best of health for it , I always read on the data sheet supplied with the rings , that they suggest using a std. tension ring in any wet sump applications.
I already have and use a vac pump............but THIS time I'm pulling vac down to no more than 6-7inches to "promote" having an oil system that actually WORKS the way its intended instead of starving bearings as its done in the past. using suction as high as 15in.
Even then I had what appeared to be evidence of oil in chambers ( very slight ).
So I thought , what the hell..............why not just go to a std. tension oil ring instead of the low tension expander they give with the set. ( Mahle ).043/.043/ 3mm.
I mean how much additional drag can a std 3MM oil ring have? Hell , I'd rather have good oil control than a potentially leaky low tension detonating power robbing slob.........and my car runs well............but?
I can't see the difference between the 2 worth anything noticeable , but I DO know the benefits of a dry chamber............

[engineguyBill]

Low (8 TO 12 LB) and ultra low (4 to 7 LB) rings will work fine in a wet sump application, as long as a vacuum pump is used. Most guys go overboard on the vacuum with a vac pump. All that is necessary is enough vacuum to keep pressure from building up in the crankcase. "Less is more" in this situation, high vacuum readings are more harmful than good.

[joespanova]

Low (8 TO 12 LB) and ultra low (4 to 7 LB) rings will work fine in a wet sump application, as long as a vacuum pump is used. Most guys go overboard on the vacuum with a vac pump. All that is necessary is enough vacuum to keep pressure from building up in the crankcase. "Less is more" in this situation, high vacuum readings are more harmful than good.

" high vacuum readings are more harmful than good "

AMEN , brother
But , what I'm looking for is an educated guess at the diff. between the 2 ring tensions. (loss / gain ).

[wyrmrider]

Joe I think it was in another thread but unless you are in some "heads up" class or circle track and there in a class where you either run all season or tear down every week I'd run the more tension
cheers

[CGT]

The last few 3mm expanders Ive gotten in ring kits, were excessively tight in the bore to me. I have a 3mm 4.005 expander in a 4.040 bore, wet sump, no vacuum, no oiling problems so far. I am currently assembling an engine with a 4.100 expander in a 4.125 bore which will have vacuum. Are you running a napier second ring?

[joespanova]

The last few 3mm expanders Ive gotten in ring kits, were excessively tight in the bore to me. I have a 3mm 4.005 expander in a 4.040 bore, wet sump, no vacuum, no oiling problems so far. I am currently assembling an engine with a 4.100 expander in a 4.125 bore which will have vacuum. Are you running a napier second ring?

Yep

[cpmotors]

Standard 3mm oil rings from TS are usually 11lbs for 4" bores.

[resurrectionjoe]

See chart in this article.


http://www.onedirt.com/tech-stories/tot ... r-classes/

[steve cowan]

I am wondering if experienced guys are still in agreement with this thread,
I am building a new 383 short block
New Dart little M sportsman block 4.030"
New JE pistons 1.2 mm,1.5mm,3mm oil ring
The 3mm oil ring pulls 10lbs on the fish scale
With a 4.000" expander it pulls 4lbs
With the Napier 2nd ring it pulls 12lbs with 4.000" expander.
These are NOT file fit rings and it has 0.003" piston to bore clearance.
Will be using my GZ vac pump.On my old motor pulled 5" at idle and 15" at WOT and it has adjustable regulator.
Engine will be dynoed,will be testing MS 109,MS 100 - 103, Sonoco 260 -260GT
This engine won't see alot of street use.
Looking for feedback on the 4lb oil ring
Thanks in advance.