How to find the right Automotive Replacement Rods & Main Bearings for Engine Kits AI guide

Written by an AI model from its trained knowledge.

What the AI looks for in Automotive Replacement Rods & Main Bearings for Engine Kits

Journal size: Micrometer every journal. Order standard or the exact undersize the crank was ground to, often stamped on the crank or noted by the machine shop. Bearing undersize must match the crank grind, or the oil clearance will be badly wrong.
Oil clearance: Verify with bore gauge and micrometer, or Plastigage, against factory spec. A common rule of thumb is about 0.001 in per inch of journal diameter. Too tight a clearance wipes bearings, and too loose a clearance drops oil pressure.
Bearing construction: Use bi-metal bearings for stock street rebuilds and tri-metal bearings for high-load or performance use, per the bearing maker's guidance. Tri-metal bearings carry more load. Bi-metal bearings tolerate debris embedment better.
Thrust bearing and end play: Confirm the thrust bearing position and measure crankshaft end play after torquing. Thrust location varies by engine, and incorrect end play damages the thrust surfaces.
Rod bolts and resizing: Replace rod bolts on reconditioned rods, and have the big-end bores checked for roundness and size. Stretched bolts and out-of-round big ends ruin new bearings regardless of bearing quality.

Clevite: MAHLE bearing line, a reference for stock and performance rod and main sets.
King Bearings: Wide range of rod and main bearings, including performance lines.
ACL: Bearing maker known for its Race series and import coverage.
Sealed Power: Common bearings in stock rebuild kits.
Eagle Specialty Products: Aftermarket forged rods for performance builds.
ARP: Rod bolts for reconditioned or upgraded rods.

Only if journals are scored, tapered or out-of-round beyond spec. Otherwise polish and use standard bearings.