I borrowed a book from a guy at my work (Title: How to Build High Performance Chevy LS1/LS6 V-8's - Modifying and Tuning Gen lll Engines for GM Cars & Pickups; by Will Handzel).

I've started reading it and there's a section discussing the oiling system and it reads as follows points of interest in bold:

"Oil control is very important to GM as higher oil pressure ties up horsepower in pumping losses and increases oil consumption, which can lead to higher emissions. Because of this, any performance upgrades should be accompanied by increased spring pressure on the oil bleed-off spring in the oil-pump outlet to insure maximum oil flow."

Not that I'm any expert but I've never heard of this and wondered if anyone has done this, what exactly is involved, etc.

 

Most of the aftermarket and ported pumps come with a stiffer spring or a shimmed spring to increase the amount of pressure the pump will create before the bypass opens. I don't think the added pressure is really as big of a deal as that makes it sound. As long as you have decent oil pressure now I wouldn't go through the hassle of messing with it.