Fuel Pressure Issue

[collierj]

Hey guys, have a little problem with my fuel pressure being to high. I have a bigger intank pump, and running pw surge with duel walbro 460 pumps on eflex. my pressure sits on 70 at idle. Can anybody give me any tips on getting this down. I cant seem to figure it out.

[gaz097]

What reg are you running and how is it hosed? Is it the standard rail still

[collierj]

its a 1200 reg that comes with the kit, standard fuel rail

[gaz097]

Correct me if I am wrong. The return line off your rail goes to the reg then from the reg back to your surge? If so it sounds like you need to upgrade or modify your return line from the surge to the fuel tank. I modified the intank pump return by removing all the restrictions in the swirl pot and got the pressure a little lower but 10psi is optimistic

[45T-XR]

When you say you have 70psi at idle is that with the vac line attached to the reg or is that base fuel pressure?

How are your twin pumps wired, are they run sequentially off a hobbs switch or are they full time? Ive got stock return size with a holley 12-1800 and fpr1200. But I stage the second pump off a hobbs. Set the base fuel pressure with the vac line off the reg at 4 bar/58.5psi and see if you have enough adjustment in the reg. If you dont then you are limited by the size of the return most likely, staging might help but it is really only trying to cover up for lack of return size.

[Kosij]

I run twin 044's with standard return line! Highly doubt that's the issue. I would be looking at the return line from the reg to the surge tank, make that a -8!

[collierj]

yes it is. I installed it exactly how the instructions came from pw. then gave it to tuner for a tune. but we just cant seem to get it down. I might try the vaccum line

[gaz097]

  On 29/07/2014 at 1:08 AM, Kosij said:

I run twin 044's with standard return line! Highly doubt that's the issue. I would be looking at the return line from the reg to the surge tank, make that a -8!

Walbro 460 flows a fair bit more then a Bosch pump Kosij. And I run an -6 line back to my surge and and standard return to tank and can get down to 2 bar minimum. Twin 044's as well Edited 29/07/14 02:18 AM by gaz097

[IH8TOADS]

  On 29/07/2014 at 1:08 AM, 45T-XR said:

When you say you have 70psi at idle is that with the vac line attached to the reg or is that base fuel pressure?

How are your twin pumps wired, are they run sequentially off a hobbs switch or are they full time? Ive got stock return size with a holley 12-1800 and fpr1200. But I stage the second pump off a hobbs. Set the base fuel pressure with the vac line off the reg at 4 bar/58.5psi and see if you have enough adjustment in the reg. If you dont then you are limited by the size of the return most likely, staging might help but it is really only trying to cover up for lack of return size.

Keep in mind that If it's setup as a twin feed rail you can't run one pump off a pressure switch so keep that in mind!! You would need to control both pumps simultaneously....if each pump has a separate feed line anyway! Edited 29/07/14 03:33 AM by IH8TOADS

[Ralph Wiggum]

^whs at very least you would need check valve on the secondary pump to prevent the main pump pushing fuel back through it and bypassing the reg.