fuel pressure

[dlange]

What is the highest safe pressure to run. I am at 21 running and about 26 idle. I think I may need a regulator? But I have had no hard starting problems. Any opinions.

 

[KLockliear]

You're fine.

 

[dlange]

Thanks Keith, the pumps rated at 15 but she sure gets it up there.

 

[ToolManTimTaylor]

in the 28 - 30 inlet PSI the Vp44's internal seals can fail. I have seen my setup before the Pe~Pump conversion spike as high as 29 But all is still fair in love and war tho

 

[ToolManTimTaylor]

in the 28 - 30 inlet PSI the Vp44's internal seals can fail. I have seen my setup before the Pe~Pump conversion spike as high as 29 But all is still fair in love and war tho

 

[KLockliear]

We have not seen any problems at those pressures, or higher pressures for that matter.

 

[RSnaith]

We've had a couple customers who have had seal failure while running 28+ PSI fuel pressure.



I'm not sure why you'd ever want your pressure that high in the first place. A properly designed fuel system should deliver stock pressure, or at least near stock pressure at idle, and should not lose much more than a couple PSI at WOT. That way you KNOW that you are not having a fuel starvation problem. Remember, Bosch has a 19 PSI cutoff built into the pump, and there is obviously a reason they decided to do this. Open up the lines to a good size, toss the pusher pump in the trash, and run with a good single pump that has a max pressure of around 19 PSI.



Rod

 

[EricBu12]

I would definately get a regulator. I put in a mechanical adj. regulator. I can go higher or closer to stock.



The return goes to the inlet of the Filter back by the tank so now the Pusher Pump (7# Carter) don't work hard with the small PSI on its inlet.



I was over 20 PSI with the 2 pumps but now I have 12-14 PSI over all the spectrum Even WOT.

 

[KLockliear]

With the installation of our camshaft in our old white 24v, that truck now had a 12v lift pump lobe. We retrofitted the 12v lift pump to that truck and ran that system with no regulator. That truck will make 55psi at idle and no less than 45psi at WOT making around 475hp.



We have seen absolutely NO problems from this truck and this setup, which now has over 25k miles on it with a stock VP44. The driver actually reported that throttle response is better with the higher pressures.



It can be done, has been done and is not a problem.

 

[RSnaith]

Originally posted by KLockliear

The driver actually reported that throttle response is better with the higher pressures.

We noticed similar results, although it was only on trucks that would have about 400 BHP at the rear wheels, and it was only noticeable once we hit 13 PSI at WOT. Any further pressure increase did not yield any better throttle response. We did some timing runs, and found a hair better acceleration, but we didn't have a chance to dyno. We also noticed a 2 PSI gain in boost at the 13 PSI mark.



Did you guys get a chance to try it out on the dyno?