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Learn Me On Returnless Fprs.

StealthX

By StealthX,
in Engines & Forced Induction

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StealthX Veteran

StealthX

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Posted (edited)

Hey.

Looking to upgrade my fuel system, and my car has a returnless fuel system. My stock FPR in the tank is not up to the job of making anymore power.

I need a non-return, boost referenced FPR.

Would this work? Here on eBay

That aeromotive one has one inlet and three outlets, so in theory i should be able to use that in a returnless system right?

Like this:

fpr.jpg

Yeah? Any other models of FPR that would work? Basically I need something with an inlet, outlet AND a return.

Thanks.

Edited by turbo x-trail
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StealthX Veteran

StealthX

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Edit:

Why cant u run a return line?

The stock system is returnless, and there's no extra fitting on the end of the fuel rail to run a return back to the tank. And as far as I've seen, there's no aftermarket companies that make a return style fuel rail of good quality.

That will work fine - my pick would be a sard or nismo regulator. Stay well away from turbosmart.

Got to ask - whats wrong with whats already there? Have you run out of fuel pump?

Nah I've run out of FPR flow. The stock FPR in the tank isn't boost referenced and I'm guessing it's running out of flow and the pressure is dropping at around 13psi on this set-up. Max boost sees 76% duty cycle from the injectors, and I've got a genuine 500hp walbro in the tank. The only other link in the chain is the FPR, so logic says it isn't up to scratch.

Cant you run a new braided fuel line and use the stock one as the return Cam? What does the stock fuel pump setup look like?

Stock set-up is a pump, filter and FPR built into the fuel canister. Pump receives a constant 12V (have checked it), base fuel pressure is 3.5bar, and the line's size is 7.95mm (5/16th)...

p.s. thanks for replies fellas!

scotty nm35 Grand Master

scotty nm35

Posted
Posted

I would just braze a stainless dash fitting on the closed end of the rail and reverse the flow, run a referenced reg off the stock line in the engine bay, a new pump bracket and braided feed line and you are done.

A stainless plate for the tank with the fuel fittings, insulated connectors and pump hanging off it would be good, as im sure your pump assembly is plastic like mine right?

StealthX Veteran

StealthX

Posted
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I would just braze a stainless dash fitting on the closed end of the rail and reverse the flow, run a referenced reg off the stock line in the engine bay, a new pump bracket and braided feed line and you are done.

A stainless plate for the tank with the fuel fittings, insulated connectors and pump hanging off it would be good, as im sure your pump assembly is plastic like mine right?

Woah that's a huuge job!

Wouldn't it be just as effective to run the FPR and utilize the stock line, like my amazing paint drawing described? I've heard the limit for a returnless system in the Sentras (same engine, car in the US) is about 400hp.

I'm nowhere near that at the moment. It should work returnless no problems. I wanna avoid going to a returnless system as much as possible, it would be a karnt of a job, and I can't justify doing all that work if i'm not planning anymore power down the track...

StealthX Veteran

StealthX

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Posted

Dude, you just put a turbo in. How is a fuel line and reg too hard. :P

True hahah... Only problem is this car is my daily, so intake manifold off, fuel rail out, sending fuel rail off to be welded, running a return line down the back, tuning it all on the street etcc.. would take more than a weekend!

But from what I see, it'll work just the same return or returnless.

Scotty do ya reckon the aeromotive FPR I linked above would suit? I've found a good seller on eBay and a good price! From what I hear they make good gear, and it's got the right number of inlets/outlets...

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