Champion RC42S Spark Plug
Specs, cross-brand equivalents, vehicle fitment, and live prices for the Champion RC42S.
The Champion RC42S is a 14mm thread, gasket seat, copper electrode spark plug. These specifications are decoded from the Champion part number and determine which plugs it safely cross-references to — a valid equivalent must match the thread, reach, seat and heat range.
Cross-reference equivalents
| Brand | Part | Metal | Buy |
|---|---|---|---|
| Denso | IWF20 | Iridium | Buy |
| Denso | W20FPR-U | Copper | Buy |
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