JP, .0025" is about right. .003" is probably good....but when you get past that, the clearances are gonna be big.
I wouldn't worry about it....I'd say a race engine running at high revs for lap after lap would have a shorter life span. A street car is a different story in my eyes.
But it also makes sense to me that you would need a little more pressure in an engine with larger bearing clearances. If you can picture the film of
oil the rotating assemblies ride on, if you have a bigger clearance, there's more chance of the assemblies "wobbling" back and forth in the journals if there's insufficient
oil pressure to keep them in their place.