Description:

General Motors Clevite H-Series 77, Tri-Metal Main Bearing Set fits the following:400 CID (6. 6L) Chevrolet V8 cylinder 1970-1980 (High Performance). NOTE: Engines Using 400 Crankshaft, H-Series Performance, Grooved Upper Halves Plain Lower Halves. Clevite Main Bearing Set part number: MS1038H1 (0. 001in. / 0. 026mm Oversize)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 main 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). 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. Instead, the bearings will be narrowed in plof the enlarged chamfer to provide greater crankshaft fillet clearance. The new narrowed bearings will be avail Model # MS1038H1 Features: Main Bearing H-Series 0. 001 in Undersize.