fuel pump/boost psi questions

[foxracerb52]

hey guys i have a couple of questions. I recently bought a 1995 talon tsi with a 16g turbo. When I bought the car the guy gave me a walbro 255 fuel pump and said he was going to put it in. I was wondering if i could install the fuel pump with out putting in bigger injectors? Right now the car is running at around 8-9 psi i was also wondering if i would be able to turn it up?

 

[born2tune]

sweet,
you can install your walbro without having the need to get bigger injectors, because stock injectors can push upto 450cc's so if you have a walbro in with stock inj, its still going to push 450cc, just that the fuel lines will have a true-feed positive pressure at all times, in other words, you will never experience fuel starvation or "fuel cut" BUT this fuel cut can be avoided by not pushing more than 15psi on stock injectors because you will have a unstable or bad fuel/air ratio thats waaaay to much air "pressure" for your stock injectors to compensate sending fuel, which will cause fuel cut, "feels like hitting a brick wall", so thats when you get bigger injectors when u wish to push over 15psi (i got evo3 16g and i run 15psi all day!!!!)

so in short:
yes you can install your walbro 255 with no problems or side effects, (might want to look up the re-wire mod{ensures your walbro has 12v current at all times without suffering voltage starvation which happens to all stock fuel pumps)

with stock injectors you dont want to push more than 15psi, because you will mess up your stock internals due to lack of fuel.

hope this helped

 

[TSi Kid]

also with getting the 255 it would be in your best interest to get a
fuel pressure regulator(fpr)

 

[DSMopar]

Ummm ignore the first poster, listen to the second.

The only issue with running a 255 is regulator overrun which will cause rich idle.

 

[crazyquik22023]

ya if i was you i would also get a FPR if you upgrade fuel pump or injectors

 

[dsm8883]

fpr and i would check the fuel filter for replacement.

 

[foxracerb52]

If i put in the fpr, the walbro fuel pump, and 550cc injectors what do you guys think would be a good/safe amount of boost to run?

 

[welfle18]

Well you cant just through bigger injectors and expect the ecu to figure it out. You need to tune them with some sort of device. That is were ecmlink comes to play or for the cheaper route you can get an afc. You would only know how much boost you could run if you had some sort of logging device to tell you what your injectors were running. Usually the accepted value of 80%.

 

[foxracerb52]

ok to end this thread for now with the stock fuel pump, injectors and the 16g turbo... do you think i can turn up the boost to 15psi without running into problems?

 

[DSMopar]

I wouldn't....

14b yes... 16g no.... I'm sure many have but it kinda depends on the weather and your intercooler.... for safe measure though I'd stick around 14 or lower until you get fuel mods.

 

[spyderturbo007]

ok to end this thread for now with the stock fuel pump, injectors and the 16g turbo... do you think i can turn up the boost to 15psi without running into problems?

That depends.

Whenever increasing boost, you need to have some type of logging device. Without one, you have no idea what is happening and can easily blow your motor. Once you get one and do the upgrade, we can take a look at the logs and determine the safest boost pressure to run.

Upgraded injectors are always a good idea when flowing more air.