Fuel pump question
#1
Fuel pump question
Hey I just did a TII swap. I left the NA fuel pump. My buddy had a walboro 255 that he sold me for cheap so I took it. I'm wondering if I can just swap this in without doing any other mods to the car, or should I get a new fuel pressure regulator or bigger injectors etc.
It's a basically stock S5 jspec, intake + catback. Running about 11-12 psi max but not constantly.
It's a basically stock S5 jspec, intake + catback. Running about 11-12 psi max but not constantly.
#2
Longtime Lurker
How are you running 11-12 psi with just a stock s5 jspec? I have same setup with Full RB exhaust and im 8.5 or 9 max...
You can keep your stock injectors and just put in a walbro255 or FD pump. If youre running that high though I would guess it is safer to have the bigger injectors.
You can keep your stock injectors and just put in a walbro255 or FD pump. If youre running that high though I would guess it is safer to have the bigger injectors.
#5
Top Down, Boost Up
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If you've run under boost with an NA pump, I can almost guarantee you that the engine has been detonating. The NA pump flat out does not work under boost; the flow rate is practically 0 at high fuel pressures. It's time for a compression test to find out if the seals are on their way out.
Walbro pumps are drop in. You will definitely have it overwhelm the stock FPR, but it's manageable. Fuel pressure will increase across the board, so your idle may get extra rich. A walbro by itself is the BARE MINIMUM to run 10+ psi on the stock turbo. You need bigger injectors, fuel control & a wideband to truly have a safe build. Anything else is a gamble.
Walbro pumps are drop in. You will definitely have it overwhelm the stock FPR, but it's manageable. Fuel pressure will increase across the board, so your idle may get extra rich. A walbro by itself is the BARE MINIMUM to run 10+ psi on the stock turbo. You need bigger injectors, fuel control & a wideband to truly have a safe build. Anything else is a gamble.
#10
Top Down, Boost Up
iTrader: (7)
Don't give people this crappy advice. I've been down the blown engine road twice after running 10 psi on a stock fuel system. Pushing the engine on stock fuel is a noobie mistake. One that cost me when I was getting started, and one that I see far too many people making still.
#11
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I use a Walbro 255, the rich idle doesn't bother me, as long as it runs, and mine runs perfect when under boost and cruising. I've retained the stock fuel pump relay, but have rewired and relocated it to the back, and run heavier wire.
I run 8-9 psi though, don't need anymore for taking out the trash thats around here.
I run 8-9 psi though, don't need anymore for taking out the trash thats around here.
#12
Longtime Lurker
If youre hitting 14psi on what you believe is a stock setup, then maybe you have a boost creep issue. You should really find out whats going on with you car
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trickster
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