RINGS 1/16 or .043

J.Toney wrote:So for tools like me, it much more than a matter of actual ring thickness, or even usage. Good thread and thansk for the input guys!

YEA ... as in other parts of the engine it is the entire COMBINATION which rules.
Usually a thinner ring has less tension, is lighter and more flexible however, THAT is not always the case.

I have personally run both ring setups at 4.625 and 4.675 with no bad results either way. Both of these applications used radial gas ports and relatively low tension oil rings with a dry sump and considerable crankcase vacuum.
It would be an interesting, however expensive A B A dyno test for the future.
The 618 has the skinnier rings and based on its performance, I will probably go that way on the 4.75" stroke engine that is on the drawing board.
Just my input...
Keith

Wheelie58 wrote:I have personally run both ring setups at 4.625 and 4.675 with no bad results either way. Both of these applications used radial gas ports and relatively low tension oil rings with a dry sump and considerable crankcase vacuum.
It would be an interesting, however expensive A B A dyno test for the future.
The 618 has the skinnier rings and based on its performance, I will probably go that way on the 4.75" stroke engine that is on the drawing board.
Just my input...
Keith

C'mon Kieth ... not really a normal street/strip/bracket engine there.   
With a 4.750" stroke, 65 ft/sec is reached at only about 5,000 RPM so, I would say a thinner .043" top ring with about .170" radial maximum would certainly be in order.

rmcomprandy wrote:

Wheelie58 wrote:I have personally run both ring setups at 4.625 and 4.675 with no bad results either way. Both of these applications used radial gas ports and relatively low tension oil rings with a dry sump and considerable crankcase vacuum.
It would be an interesting, however expensive A B A dyno test for the future.
The 618 has the skinnier rings and based on its performance, I will probably go that way on the 4.75" stroke engine that is on the drawing board.
Just my input...
Keith

C'mon Kieth ... not really a normal street/strip/bracket engine there.   
With a 4.750" stroke, 65 ft/sec is reached at only about 5,000 RPM so, I would say a thinner .043" top ring with about .170" radial maximum would certainly be in order.

.135 radial even better

Trying to decide on a ring package , been looking at the 1/6 back cut top ring or a D wall .043 and a back cut .043 3 1/6 standard oil ring and have not decided on the 2nd ring , a local guy told me to use a back cut .043 with gas ports , the engine is a 562 nitrous build , any input on this ,
motor does not have a vacuum pump

Hate to say how long my 043's have been running still sealed tight..............

Does a .043 ring setup require a vacuum pump and or gas ports? Which gas ports work better? Through the top or above the top ring? Just wondering what the thoughts are on this.

460pulling wrote:Does a .043 ring setup require a vacuum pump and or gas ports?  Which gas ports work better? Through the top or above the top ring? Just wondering what the thoughts are on this.

NO ... no pump needed at all with standard tension .043" rings.

ok thanks.

Ace ,
I'd run an 043x043x3.mm ring pack with some lateral gas ports whit your combination and where you run. That would be the lowest drag best sealing combination. Use back cut rings on both top snd second positions. They will last for a few hundred passes.

Ok, I'm trying to get some pistons built (Diamond) and having some challenges determining the best ring pack to ask for. 4.600 x 4.5 (6.8 rod) nitrous (5-600 shot) drag engine. Less than 100 passes per year. The plan is to have lateral gas ports added. The engine has a good vacuum pump, but will be wet sump. I plan to use Ackerly and Childs rings.

This seems to be what my research has determined. Please weigh in if you think it should be different. What can I expect for longevity/durability?
.043 back cut HTD top
.043 napier style second
1/16 oil standard tension

460dave,
Ackerly and Childs are good peiople to deal with. Make sure the top ring they supply you is not a moly faced ring as you are spraying too much NOS for moly to survive. A napier second ring wouldn't hurt either. Give the rings plenty of gap ,a factor of .007/inch of bore should be fine.

The HTD top ring he listed is an A&C NOS ring.