How to Select Piston Rings

above the ring and between the ring’s inside diameter and the piston groove, the ring is forced downward and outward, creating a tight seal over a wide range of engine rpm. Most of today’s OE compression rings feature a premium grade cast iron, ductile iron or steel alloy coated either with a heat resistant plasma-molybdenum or chromium facing material. “Plasma-Moly” is a relatively ... ................
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