Is there a different hone needed for moly coated rings vs cast OE ductile iron rings?

Originally posted by RegaMaro:
Is there a different hone needed for moly coated rings vs cast OE ductile iron rings? Cylinder finish for moly rings we use a Sunnen 623 stone and plateau hone with a C30-C03-81 for 3 or 4 strokes and this is done on a Sunnen 616 cylinder king and all our blocks our torque plate honed and as far as cast rings we would not use the plateau finish.

Rega,
Generally, you will find that OEM cast rings are grey iron, not ductile. Ductile iron is usually used for premium top compression rings, with moly or chrome facing. And yes the cylinder hone procedure is different for moly-faced rings, as CNC has pointed out. The cylinder finish would also be different if a chrome-faced ring were to be used.

ok, good. thx for clearing that up for me guys

Just to add to the confusion, here is a link to Hastings' Service tip (http://www.hastingsmfg.com/Service%20Tips/cylinder_bore_refinishing.htm) on surface finish. Note the CYLINDER ROUGHNESS section.