1959 – 1964 Olds 394 CI Piston Rings

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May 29th, 2017, 11:15 PM

rocketbob54

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Join Date: Jan 2014

Location: Colorado

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1959 – 1964 Olds 394 CI Piston Rings

Through much frustration I searched for a set of piston rings that would fit my new 394 OE size pistons. For some unknown reason to me the Olds engineers chose to use two different thicknesses for the top two compression rings. The top ring is 5/64” and the second ring is 3/32 “ thick. The bottom oil ring is 3/16” and is not a size problem. The problem with the two compression rings is that most ring manufacturers have discontinued making the OE sizes and have gone to two 5/64” compression rings. I was told the reason for this is to fit new aftermarket pistons that require the same size compression rings. So what's a guy that needs a set of OE size rings to do? Hunt and pray a lot I guess. The only new aftermarket pistons that require the two size OE ring set that I know of are made by EGGE Machine which I purchased before I learned about the ring manufacturer size change. I must say EGGE pistons are a work of art. But finding rings in the OE sizes is most difficult. And then throw in the dimension oversize and ring material. EGGE does sell Grant rings in the OE size but I bought a set and had to return them because the oil rings were too big. I also don't like the way the Grant oil ring expander ends are supposed to butt up to each other. There are many chat boards on line that have guys expressing about having the same problems with Grant oil rings. I was able to purchase a ring set of Moly Sealed Power .030 in the OE sizes from NAPA but when I inserted the ring in the cylinder to check end gap I found they were for a 371 with a 4 inch bore. So I had to return that set. Back to the computer and more searching resulted in finding a Hastings 651 .030 OE size set at a place in California called Perfect Engine. They are expensive but I ordered a set. I wanted Moly rings but I was told Hastings only makes the 651 set in Iron, but if they are the correct size they would have to do. Then I found out Perfect Engine was out of stock and they will have to be shipped by the factory. Once again I was holding my breath. Luck was on my side this time as I received the correct set in 5 days. I hope this bit of information will be of some help to anyone re ringing or doing a rebuild on a 394 Olds engine.