CRG Discussion Forum

Camaro Research Group Discussion => Maintenance => Topic started by: 69-er on August 22, 2009, 03:18:48 PM

Title: Moly or Cast Rings?
Post by: 69-er on August 22, 2009, 03:18:48 PM

I have an old SBC that is maxed out at 0.60” over.  It has about 70,000 miles since it was rebuilt.  Several thousand miles ago, I tore down the motor and did a quick hone and ran the motor with no apparent blow-by problems.  (On cold mornings, it does sound like a diesel!  Piston slap?)  I can’t remember what type of rings I used.

 

For other reasons, I have torn down the motor again and I’m going to try to do a hone one more time.  I have no idea what the actual taper is.  There is very slight ridge I can feel, with the sides of the cylinders being a little less, so I know there is an out-of-round condition.  I can still see a lot of the original cross hatch on the walls, but the pattern is irregular and somewhat patchy.

 

Since this is not the correct way to be resurfacing the cylinders, I was wondering what would be the best ring to use that could tolerate the irregular wear.


Thanks!

Title: Re: Moly or Cast Rings?
Post by: JohnZ on August 24, 2009, 08:59:52 PM

All rings are cast - moly just refers to the molybdenum-based facing applied to the contact surface of premium rings (vs. the chrome facing on older rings that took forever to seat). I think moly-faced rings would be better, as they will seat faster (assuming the hone pattern/surface is done per the ring manufacturer's instructions).