Speedway Motors has all the parts you need to rebuild your Flathead Ford V8, including these high-quality main bearings and aluminum bi-metal rod bearings. Precision-built to the high standards demanded by today's rodders and restorers, these silicon bi-metal bearings main bearings and insert style rod bearings come in .010" undersize.

Crankshaft Main Bearings:

• Improves Crankshaft Finish: Silicon particles reduce/eliminate microscopic ferrite peaks on improperly ground/polished nodular cast iron crankshafts.
• Wear Resistance: During engine operation, silicon particles round off crank journal high spots, reducing friction and related wear.
• Improved oil clearance: Because of reduced wear, silicon bearings make it possible to maintain OE clearances over the life of the engine, which reduces operating noise, vibration, and excess oil flow.
• Tolerance Control: All shells matched to ± .0001" vs. the competitions' ± .00025"
• Temperature Threshold: Silicon bimetal material melts/flakes at 662° F vs. tri-metal at 365° F.
• Corrosion Resistance: Defends against corrosion caused by unleaded fuels and moisture.
• Environmentally Friendly: All KING silicon bimetal engine bearings are "Lead-Free".
• O.E. preferred material: Most O.E. engines today use and enjoy the benefits of silicon bimetal bearings.

Insert Rod Bearings:

•  Tolerance Control: ± .0001" vs. the competitions' ± .00025"
• Superior Embedability: Material is much thicker than Babbitt overlays (.012" vs. .0008"). This provides greater macro-particle (> .0004" diameter) embedability. Macro particles are most responsible for scratching  crank journals & tearing/weakening babbitt overlays.
• Temperature Threshold: Bi-metal withstands 662° F (350° C) compared to tri-metal 365° F (185° C). Affords greater protection against localized overheating due to misalignment, detonation, overloading, loss of coolant, etc.
• Conformability: Minimum depth of .012" enables greater adjustment to bore or journal misalignment without causing bearing failure or journal damage.