The only difference between a stock and high pressure pump is the regulator spring. The rotors are the same. I have used high pressure pumps for years on worn engines as a band aid for customers who didn't want to rebuild engines but wanted the oil light out. It works. I'm not basing my opinion on a bunch of who shot John online theories. I know what I'm talking about, because I've done it. A lot. Now, the high volume pumps are a different animal. They do have deeper rotors to move more oil.