MSefi.com read only forum (Jan.15,2018)

Ihave a few questions regaurding fuel pressure and the regulator. First off I am currently running a stock GM regulator on a 3.1 SFI. What should the pressure be at idle and should the pressure rise as I go from vacum to boost. Then, just to double check the regulator should be on the return side. Now what I am trying to accomplish is raise the pressre from 43lbs to 70 lbs, What I have is an inline vacum activated ajustable regulator that I want to put inline after the stock regulator pump both to 8 lbs then adjust the pressure to 70 lbs. Any thoughts ? Will this work ?

Thanks
blatzy

I'm not sure I can help you any here but here goes:
You should have the fuel pressure increase as you build boost, usually raising 1:1 with the boost pressure. This keeps the relative pressure the same on both sides of the injector. As far as running 2 regulators, I don't understand this, nor do I think it would work as the lower regulator will override the higher. Yes, the FPR goes on the return side of the fuel rail. 8psi...really??
Just my 2c.

You can get 2:1 regulators. I had a regulator that pushed my fuel pressure from 32psi static to over 90psi at only 10 pounds of boost!