Not quite sure I get how reducing crankcase pressure would reduce piston pin oiling. I would actually tend to believe the opposite. By reducing crankcase pressure, you are decreasing the air density, thereby allowing oil slung from the crank to travel faster and farther. The picture that comes to mind is putting a feather in a vacuum, it drops like a rock, due to the lack of aerodynamic friction. the reduced pressure would also improve oil quality by lowering the boiling point of water. Interesting enough is that piston ring sealing is shown to be improved with lower crankcase pressures. Looks to me like I may be running an experiment next season.

I am going to be running Total Seal MAXXSeal rings on this rebuild. I don't foresee a blowby problem with those but a little extra HP never hurts. I toyed with the idea of a vacuum pump on the previous motor due to the hardened race rings it used to help them seal.