I have a block that has the crank bore honed out to the outer limit of factory spec but am concerned about using it for a mega performance build as it may (or may not) increased the chance of spinning a main bearing with the reduced crush.

Has anyone had any experience with this?

I can't afford to build this motor twice so am considering whether I need to find another block or not.

 

mega performance build== no if you are gonna be on the edge with limits and clearance
you are risking too much

 

Sell that to someone looking for a close to OEM build and find another for yourself