Top ring in second position?

[John B]

What happens if you run a top ring in the second groove? :confused:

[Speedeuphoria]

alot of times they are different thicknesses so it could cause the ringland to fail when it expands some

[turbovanman²]

On our engines, there the same size so what will happen is a few things. You'll have bad compression that probably wont' show up unless the engine is running, you'll have lots of blowby, oil burning, ring flutter and you'll probably need more boost than before as your loosing it into the crankcase. You will also have lots of oil leaks and can't keep oil INSIDE the engine due to the internal pressure.
Another possibility is it might be ok but the 2nd ring isn't designed to take the heat and load so it might melt down pretty quickly, :(

[John B]

In case you're wondering why I'm asking, I have a set of total seal gapless top rings that I KNOW won't hold up in the top ring position. I wonder if I could get away with using them in number two?

[turbovanman²]

No, the 2nd ring can't take it.

After my last mess with those gapless rings, never again for a turbo engine, :censored:

[zin]

They might work o.k., but remember that rings seal by way of a pressure difference between the top and the bottom of the ring, so if the 2nd ring seals too good, it might unload the top ring, making the 2nd ring take the load of the top ring. I don't know that it would be a problem in our application, but it is enough of a problem on high HP nitrous engines that many engine builders will purposely run an extra wide 2nd gap to allow some of the gases to vent and thereby keep the pressure differential needed to keep the top ring working. Food for thought if nothing else.

Mike