<< C'mon everyone, let's get out of the dark ages.
 > In a few months, I may have a conversion kit (cheap) for
 > experimentals that any decent machine shop can employ.
 > Starting with O-320 & O-360 Lycs.
 > Nuff said!
 > Archie >>

Could that be a stepped gap molly filled top ring? a barrel faced dykes
second ring with a gapless spacer, like a total seal?  I would use a

spring

powered cast oil scraper. Looking for zero leakdown? Almost no drag.

What

will your kit include?
Lynn E Hanover

No, I spent time with those, and was not "totally" happy with the results.
I generated my own ring set, (still room for improvement), through a
lot of R&D.
Cast rings are on their way out, but the improvement in aircraft engines
is substantial to warrant their application.
My first engine was an O-200 in which I welded the ring grooves, relocated
and recut to other sizes, and had planned on providing these as well,
but cannot find a manufacturer for small quantity. With my poor connections
in Brazil, cannot obtain unfinished factory-type pistons.
At present, kit will include Rings, Gaskets & Seals, Guides, Prep
instructions,
etc., and will be geared to work with existing pistons. (No chrome
cylinders.)
On hold for the moment, until shop work is caught up, or unless we discover
long term negativity.
Archie

Years ago when I raced Fiat spyders and ran the engines on a dyno, I tried the dykes in the head land position. Where the ring was even with the top of the piston. The very best power, but poor life. Next best was a Deeves (very soft)moly filled cast iron top ring oversized for the bore with a step ground into the ends of the ring so the end gap could not close up. The end gaps were zero on the top ring and .008" on the second ring. Often the oil scraper has the most drag because of unit pressure. I cut the drive spring down until the ring had almost no drag at all. After each dyno run we did leakdown and compression. 240 pounds and zero leakdown was the standard. I built the leakdown gage with a .020" gate, and ran it on 100psi. So it means something, rather than comparing the cylinder to an open window and saying it is not leaking as bad as that window as with a Continental gage.

Were you born in South America? You write very well.

Lynn E. Hanover

 
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