Chevy GM LS STD Main Bearings [4.8 5.3 5.7 6.0 6.2] don't cut corners

don't cut corners

heat-treated to the highest Rockwell hardness available

to increase flow for more performance

They are manufactured from machined steel and offer excellent valve spring location

and you can choose between plain polished

Chevy GM LS STD Main Bearings [4.8 5.3 5.7 6.0 6.2] don't cut cornersThese Speedmaster main bearings are just what you need to freshen up your engine. Why? They use silicon aluminum bi metal construction. Silicon aluminum is the choice for many of today's engine manufacturers because of its high fatigue strength and superior temperature threshold. Bearing wear is dramatically reduced and the fatigue strength is greatly improved.