Clevite P Rod Bearing STD H22A1 H22A4 F20C F22C P-Series bearings are the oldest members of the Clevite 77 performance-bearing family. They're intended for high-revving engines, especially those where the high rpm cause the rod bores to narrow. To compensate for this distortion, they have higher eccentricity and a high crush factor. P-Series bearings are built on hardened-steel backings with extra-thin overlays.