I read somewhere on here that the Base Fuel Pressure on an EVO was 43 or so and that when you add a Walboro it increases that. Can anyone verify that or provide a factual number for what the stock FP should be? I added a Perrin Fuel Rail and an FPR from EVOMOTO but the instructions said something like 38 psi at idle. Anyone ????

 

It is 43.5. That is the reference point that most all injectors are test at, etc.

It is 43.5 with the vacuum hose off and blocked off at idle.
The 38 number is with the hose on and the regulator being opened by the engine vacuum at idle. It's all relative though depending on the cams you may see more or less pressure. I would not set base presure (hose off) to anything less then 40 psi though.

 

THANK you very much. I had mine set to 38.5 with the hose off, because thats what the directions that came with the FPR I got from EVOMOTO said. IIn thier defense I will say that it is inherently a DSM install instruction so I should have asked sooner.

Thanks again man I appreciate it.