Piston rings

[kick]

Looking for some rings for my 340 that I’m freshening up. Reusing the .030 over TRW forged pistons. Low mileage since last rebuild but cylinder bores will get a hone at the machine shop. I see Hastings offers a steel top ring in some kits. What do you guys prefer? Thanks

 

[RustyRatRod]

Plasma moly.

 

[4spdragtop]

 

[AJ/FormS]

I second for Plasma Moly,.
With file-fits my Leak-Down was almost immeasurable, even before "break-in". .

 

[kick]

Just to verify. Plasma moly coating with what material for the rings?

 

[RustyRatRod]

Just to verify. Plasma moly coating with what material for the rings?

They are all cast with different coatings.....or none at all which are referred to as cast.

 

[MOPAROFFICIAL]

Just to verify. Plasma moly coating with what material for the rings?

Steel is good.
Resistance to breakage via detonation.
I run them.
MS or SM part #

 

[66fs]

As above, some call the top ring material "ductile iron".