Double Moly Rings

[earntaz]

Back in the day (60s/70s) we would use double moly rings on both SBC and BBC -- now it seems they are non-existant. Ring sets now for high perf street and some weekend race engines lean toward the moly top compression ring and a cast iron second ring -- oil ring pretty much remained unchanged it seems. TRW/RAMCO, Perfect-Circle, etc. were the manufactures that offered the double moly sets.

Do any of the "expert engine builders" here know where I can get double moly or do the single moly ring sets work just as good?

Thanks -- TAZ

[KenMaisano]

Single Moly works better, the second is just a oil scraper. I like to use the Naper second ring it scrapes well and has less tension. I did use some 1/16 and 043 double Moly back in the day and they tend to spoke on deceleration, high vacuum. On my Super Stock car I took the second ring out and only ran a .043 top and a very lower tension oil ring. No other changes the car ran .005 faster.

Ken Maisano

[firstgenaddict]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KenMaisano</div><div class="ubbcode-body">Single Moly works better, the second is just a oil scraper. I like to use the Naper second ring it scrapes well and has less tension. I did use some 1/16 and 043 double Moly back in the day and they tend to spoke on deceleration, high vacuum. On my Super Stock car I took the second ring out and only ran a .043 top and a very lower tension oil ring. No other changes the car ran .005 faster.

Ken Maisano
</div></div>

When I worked for Gas Rhonda's old Cammer engine builder we ran Total Seal Gapless on the top (2 thin rings -1 over and 1 under the compression ring) and oil control that's it. Better sealing than a 2 ring setup with much less friction. Sometimes we used short compression height pistons with LONG rods and skipped the second ring land altogether. Just the top and the oil cut into the piston
.

[earntaz]

Ken -- thanks for the reply ... I figured there had to be a reason. TAZ