What is an acceptable main bearing clearance.
01-24-2006 | 12:16 AM
#1
Thread Starter
Platinum Member
Joined: Dec 2001
Posts: 2,125
Likes: 169
From: St. Clair Shores, MI
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?
01-24-2006 | 05:22 AM
#3
Off the Radar
Joined: May 2001
Posts: 1,097
Likes: 1
From: Cape Coral, FL or Colonial Beach, VA
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
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
Last edited by Linster; 01-24-2006 at 05:24 AM.
