Reply to "Fully Grooved Main Bearings?"

I recommend fully grooved mains on anything other than a grocery getter. I was last told the Clevite fully grooved mains were only available in standard size however. I don't know if that's relaible information.

There are a few ways around this, like checking other bearing manufacturers such as King bearing. I know Denny Wydendorf modifies standard sets to make his own fully grooved mains, it would be worth it to contact him via his web site and see if he'd sell you an modified undersized set.

Wydendorf Machine

You should be able to replace the bearings without further crankshaft work. You'll have to disassmble the motor, put the bearings in the saddles & torque the caps in place, measure the ID and compare to the crank journal OD. The ideal clearance is 0.0025", with limits of 0.0024" to 0.0027".

Fully grooved mains are one of the building blocks of a lubrication system equipped for higher engine speeds. There are a few other considerations as well, for instance the proper oil pan. Something to discuss perhaps at a later time.

-G