piston rings?

[Ed Wright]

I use a Napier with 6 lbs. Dry as a bone.

[Larry Hill]

What is the correct procedure to check drag from the ring package? Cylinder vertical or horizontal, dry cylinder wall or lubrication on the wall, if lubricated with what and how much, just piston with pin and oil ring or is the rod on it too. Is it the breakaway number or the dynamic pull reading?

[randy wilson]

Originally Posted by Larry Hill

What is the correct procedure to check drag from the ring package? Cylinder vertical or horizontal, dry cylinder wall or lubrication on the wall, if lubricated with what and how much, just piston with pin and oil ring or is the rod on it too. Is it the breakaway number or the dynamic pull reading?

Dynamic pull reading what I use. And I leave the rod on, and put a Zip tie around the big end of the rod, and hook the fish scale to that.

[Ed Wright]

Originally Posted by randy wilson

Dynamic pull reading what I use. And I leave the rod on, and put a Zip tie around the big end of the rod, and hook the fish scale to that.

That's what I do. Patterson hones my blocks with his Rottler diamond hone. I've used 4 1/5 lb rings, but not as dry as 6.

[randy wilson]

Originally Posted by Ed Wright

That's what I do. Patterson hones my blocks with his Rottler diamond hone. I've used 4 1/5 lb rings, but not as dry as 6.

They're also very good. I use their piston work, but never had a block by them.

[Ed Wright]

Originally Posted by randy wilson

They're also very good. I use their piston work, but never had a block by them.

They did all my short block machine work, and sold me all the parts except the camshaft. Gordon Holloway at Comp works with me there.

[Alan Roehrich]

About 6# tangential is what I have successfully run and had no oiling. with a Total Seal Napier cut second ring.

With 3/16" rings, my usual approach is to buy open stock Speed Pro SS50U oil rings, and use bore size rails with smaller bore size expanders.

Unfortunately, Speed Pro has been bought several times over the last decade or so. They've become less and less oriented toward customer service and open stock sales, also, I've been told that as the SS50U tooling wears out, they're not going to repair or replace it. In my experience, the Speed Pro SS50U oil ring is the finest in design and quality, as well as the most friendly to the machinist, builder, and assembler.

The expander in the SS50U is what controls ring tension, and the radial width of the rail is consistent and stable, as well as easy to assemble. Not so with the Hastings/Perfect Circle oil ring with the gold expander. In near 40 years of doing this, I've never had a problem, or a customer with a problem with the SS50U. Not true at all with the Hasting/Perfect Circle.

As far as testing tension goes, my method is similar to many others. I oil the cylinder with the oil to be used when the engine is being raced, carefully wiping it until it is wet, but not completely slathered in oil. I install the piston with the oil ring only into the bore, with a pin in the piston, and the pin connected to a 0-12# scale. I then roll the engine inverted, and pull the piston from the deck toward the crankcase, and record the drag.