I searched on this but there isn't much there. I'm surprised at the lack of discussion because a spun bearing means a scratched crank, and possibly a bent rod, lots of work and money. I understand that with forged rods you want an H type of bearing because they're designed for rods that flex less? I read that the factory might put different size bearings on different journals to match the sizes you read with the micrometer, but bearings only come as sets that I've seen. If you measure .001" difference on journals, or along those lines, when do you go to another bearing size, and when does the tolerance require machining (I know the factory specs on clearance, but are those tolerances unsatisfactory for 450 rwhp+)? Other information?

 

they are all about the same.

I can tell you some stuff, send me a PM. about clearancing

 

Some of us others could use that clearancing knowledge. If you could share that with all of us, thank you.