Clevite H Series Main Bearing Set .030" CLMS909H 030

H-Series Bearings

These bearings are identified by a letter H in the part number suffix. Part numbering is based on the same core number as the standard passenger car parts for the same application. These bearings were developed primarily for use in NASCAR type racing, but are suitable for all types of competition engines.

H series bearings have a medium level of eccentricity, high crush, and rod bearings have a hardened steel back and thin overlay. These bearings also have enlarged chamfers for greater crankshaft fillet clearance and are made without flash plating for better seating. Bearings with .001" extra clearance are available for standard size shafts and carry the suffix HX" (X = extra clearance). Rod bearings are available with or without dowel holes (HD = with, H = without), main bearings are available with standard 180 degrees upper half grooving and with full 360 degrees grooving (H = 180 degrees, HG 360 degrees). Use H series bearings with crankshafts that have oversize fillets and where engines run in the medium to high RPM range. H series bearings should be used if contact patterns obtained with P series parts are too narrow. Contact patterns should ideally cover 2/3 to 3/4 of the bearing surface. See accompanying contact pattern diagrams. If you aren't sure which type of performance bearing to start with, the H series bearing will be your best choice.

Please note: Some "H" series bearings will no longer be available with enlarged chamfers. Instead, the bearings will be narrowed in place of the enlarged chamfer to provide greater crankshaft fillet clearance. The new narrowed bearings will be available with a "HN" suffix and will be replacing the standard "H" suffix part number.