I ordered a Walbro 255 lph pump yesterday and then thought I should've went with the 190 lph because I still have stock 450cc injectors.

My question is: will the 255 pump affect mileage if i'm not lead-footing it? I've read that it "overpowers" the stock FPR and gives worse MPG. Other ppl said no mileage change after installing the 255. Can anybody with a 255 pump share their results?

You won't notice a difference except for the sound

I didn't notice any change in MPG.

Hmm, isn't our fuel pump a 'power on demand' thing? I didn't think that it'd be powered all of the time...

Thanks guys. Funny, I was told that if you use a Supra pump (260 lph?) you must have an adjustable fuel pressure regulator. The Walbro has similar specs too...

Yeah I'm deciding on either the Walbro or Supra TT right now. I've heard that the Walbro 255 can get rather obnoxious under load. The stock FP is a 150 unit right? I'm wondering if 190lph would be adequate for a 14B car...

Is the Supra TT fuel pump quieter than the Walbro 255?

Stock is 100 lph @43psi before wire (140 lph after).

I emailed Tom Stangl awhile ago and he said the Walbro 190 lph is more than you'll ever need for the 14B. Rewire the 190 and it'll flow a lot more too.

I bought the 255 just in case I buy the 20G one day.

If a 255 is good enough for a 20g than when is a fuel pressure regulator required?

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91 Eagle Talon TSi AWD
My Attempt at a website

How about a walbro 255 and a boost dependant press regulator??

"Stock is 100 lph @43psi before wire (140 lph after)."

Terry, what does "wire" mean? You mean fuel pump re-wire? If so does the FP re-wire give you a 40% increase??

Sorry, yes I meant rewire. I got the flow rates from http://www.roadraceengineering.com/fuelpumptechtip.htm and http://www.vfaq.com/mods/Walbro-specs.html

Apparently, voltage affects flow quite a bit. A lot of pumps are rated @ 12 volts, but @ 14 volts they give out a completely different (higher) number.

Martin, Jeff...I know 2 ppl with Supra pumps and they say it's dead quiet. I've read similar comments on a few DSM boards about how quiet it is too compared to the Walbro 255.

AFAIK, big fuel pumps like the 255 and the Supra FP raise the fuel pressure and make you run slightly richer. The ECU compensates for the extra fuel and will trim back the injectors in the range it watches to the best of its' ability. It is recommended that you use some sort of fuel management (APEX'i S-AFC) or aftermarket fuel pressure regulator to lower the fuel pressure down to stock levels. Even with the stock, boost dependant FPR larger fuel pumps will outflow it. I'm not sure when exactly you'll need a FPR (or any other type of fuel management), but it's recommended when you bolt on larger FP, injectors, etc. to get the most out of your setup and not run too rich.

Oh yea, the Supra and 255 pumps are good for about 500+ hp.

Question... everyone keeps mentioning the Supera TT... do you mean the stock fuel pump off the car... or bought aftermarket...

It's the stock one off the car. Not many wreckers will have this, though.

Everyone keep in mind that when a statement is made like, "Walbro 255 is fine for a Frank Level 25..." that they're assuming that you have the other supporting mods to go with. (:

Besides, the B&M fp regulator isn't too expensive...

The supra pump is the one from the 3g right? Or can you use the ones from an 89 turbo?

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91 Eagle Talon TSi AWD
My Attempt at a website

The "Supra fuel pump" is the stock pump off the MKIV ('93-98 Supra Twin Turbo). The pumps off the older Supras are much smaller.

One Other question... would anyone advise using the Supra TT FP on a NT, or is there a FP out there that would work better, off another stock car...

I don't think you'll need a FP upgrade unless you start bolting on turbos and NOS. My friends Integra GSR is still using his stock FP after he installed a GReddy turbo kit (7 psi boost).

A Supra pump is already overkill for most turbo Talons running 400-500 hp. On an NT it would be over-overkill.

I suggest getting a FPR and raise the pressure a bit if you need more fuel to go with bolt-on's on an NT.

According to the #'s on RoadRaceEng ... the stock pump running at 14V will provide enough flow for:
720cc injectors at 80% duty cycle - 43psi
570cc injectors at 80% duty cycle - 58psi

Therefore, if you needed to run 660cc injectors at 80% duty, you'd need to upgrade the stock fuel pump. I think the stock pump can carry most cars quite well. But bigger is nice to have as long as it isn't too loud.

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Martin Q
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Dk Blue '90 TSI AWD (grinding Xfer case)