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What is an acceptable main bearing clearance.

When checking the main bearing clearances on my motor I found all the mains had a clearance of .0015-.0017. The crank has been cut .010 undersize. I am using clevite H series bearings on a GM forged steel crank. The block is a 454 4 bolt main. I am shooting for about 550-575 hp at 5400 rpm with twin turbos. I checked all the main bearing bores and they are in withen spec and the crankshaft is withen spec for .010 undercut. I was shooting for .0025-.0030. Is .0015-.0017 main bearing clearance too tight for a marine engine? Would there be any advantages to using this tight of a clearance?

Re: What is an acceptable main bearing clearance.

Also
You should use P bearings on a GM Crank.

They make .001+ bearings, Shoot for .0025-.003 on 1-4, And .003 to .0035 on 5