Thread: bbc running oil clearance and steel cranks

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cast or steel cranks . it dose not matter if the running oil clearance is not right. this is more useful so you do not weld the crank to the bearings. it should be check on all rod s @main s with a bore gauge. not plastigage i like the main @ rod to be on the small side of size this help bearing from hamering . this keeps the bearing crush for better seating in to the main bore and rod bore. the bearing i like are mich 77 or kings and is fare as steel and cast cranks on big blocks mid stock to 500 hp in a lite car .on nos or blown 500 hp and up with nos and blown. i have had good luck with scat 4340 for the money.but it will take only so much callies make good crank and they are a more$$. if looking for a steel crank look for non-twist forgings and a good alloy here are things to think about cast cranks are not twisted when made so there is no stress built in to the crank .cast cranks when spun can be re ground.the bearings do not weld to the crank like steel so there is less damage some times . steel cranks crack this can be from harmonics steel dose have a hi amplitude than cast so hi cylinder psi and harmonics can make it crack but steel is ease to fix and will take more twisting than cast