ACL Race Series Engine Bearings

The grades in this collection

Most of them are standard grade, for an unground crankshaft. Then come the versions with 0.025 mm extra clearance, chosen on tuned engines, where the oil needs more room to pass through and to cool. The 0.25 and 0.50 undersizes go on a crankshaft ground to the matching step.

How you check, not how you assume

The clearance is measured on assembly, with plastigauge, on every bearing separately. Do not rely on the grade written on the box: the crankshaft may already have been ground in an earlier rebuild, and the tolerances differ from block to block. The collection has measuring kits for that.

What it does not cover

Almost every reference here is a rod bearing. For mains, check availability separately for your engine.