Zero4488

iTrader: (10)

I have a couple questions about the the location and function of a stock regulator on a 98-02 F-Body. I already know it's located in the pump assembly, and I check all data and I know it reads off the return line. Now what is it referencing to adjust pressure? At WOT should the fuel pressure at the rail be increasing or decreasing? Could some one post a diagram of how the fuel pressure regulator should be hooked up to the pump assembly with all the lines, crudely drawn illustrations will be fine as long as it gets the idea across. The reason I am asking is because I used to have a fuel pressure gauge on the car and I can remember that at WOT the fuel pressure at the rail would increase, now if I hook up a gauge the fuel pressure drops. I think this might be cause my issue with the car breaking up in high rpm's being I've changed everything else including the fuel pump. I mean primed the fuel pump is in check and even at an idle everything seems fine. The theory seems to be logical. All input on the subject would be great.

-Dave

Lonnies Performance

iTrader: (16)

If you have a 3rd gen, or an LT1 car , the pressure increases at full throttle (43.5psi), but an LS1 car remaims the same at full throttle (58psi). If it is decreasing at full throttle, the pump capacity is diminished, the filter clogged, or you are making a lot of power & exceeding the line capacity (which is unlikely unless you are over 600rwhp.)

I do not have pictures, but there is a t-fitting after the fuel filter, that goes back to the return/regulator in the tank. It is essentially trying to maintain 58psi after the filter, by dumping the excess flow back into the tank.