Scott Fisher notes:
<If the rod bearing journals are supposed to have a clearance
of 0.01" to 0.027", you do what Kaeding did to my crank and grind
them all to 0.01" for maximum smoothness.>
DON'T DO THIS! Actually, your machinist won't let you!
Bearings run in the 1-2 thousandths (of an inch) range.
Scott misplaced the decimal point and meant to say:
".... a clearance of 0.001" to 0.0027".
On the other hand, I once had a 948cc Bugeye crank machined to have .003"
bearing clearance, used straight 50W Castrol and the engine revved very
freely. It was in
an autocross car and not intended to last a long time, although I never had a
problem with it in 4 years and then sold the engine to a friend who used it
many
more years.
George Haynes
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