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Fpr Set Up. What Is Base Pressure? When Do I Set Base Pressure?

Muffins 34

By Muffins 34,
in Engines & Forced Induction

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Muffins 34 Rookie

Muffins 34

Posted
Posted

Alright I've been googling fuel pressure reg set up over the past few days in order to set up my Tomei Type L FPR on my R34 GT-T. Unfortunately I've been coming up with conflicting information.

1. What is base fuel pressure? I've found answers ranging from 34psi - 43.5psi

2. When do I take the reading of base pressure?

Is it at idle?

Is when the key is turned to accessory and the pump has primed?

Do I need to block the vacuum line?

3. Please refrain from telling me to keep the standard regulator. That is not the question I am asking.

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

and I suggest taking that FPR selling it and buying something better like a Turbosmart FPR1200 or so.. even those SX FPR seem ok (according to my mate that works on EVOs)

Those Tomei FPRs "may" work, but they don't control pressure smoothly when you connect a fuel pressure gauge on them.. Whenever you jab the throttle on and off quickly you can see pressure spikes and drops all over the place making your transition throttle terrible and on the odd time you'll get massive rich spots causing either misfires OR massive backfires.

Muffins 34 Rookie

Muffins 34

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Set it to stock pressure. 43.5 at idle with vacation line removed.

It will drop when line attached.

Thank you. All done.

and I suggest taking that FPR selling it and buying something better like a Turbosmart FPR1200 or so.. even those SX FPR seem ok (according to my mate that works on EVOs)

Those Tomei FPRs "may" work, but they don't control pressure smoothly when you connect a fuel pressure gauge on them.. Whenever you jab the throttle on and off quickly you can see pressure spikes and drops all over the place making your transition throttle terrible and on the odd time you'll get massive rich spots causing either misfires OR massive backfires.

Really? That seems strange for Tomei.

I'll have the tuner check while the cars on the dyno and if thats the case I'll grab a Turbosmart one off the shelf.

Thanks for the warning!

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

Thank you. All done.

Really? That seems strange for Tomei.

I'll have the tuner check while the cars on the dyno and if thats the case I'll grab a Turbosmart one off the shelf.

Thanks for the warning!

Plug up a fuel pressure gauge and watch it jump up and down on hard throttle or when the boost ramps up like a mad man.

Thing is 90% of Tomei FPR on the market are fake and even the real ones aren't that good either... A friend I regularly go to the track with swaped out his so called genuine Tomei FPR (bought from Nengun) for a Turbosmart FPR1200 and now he is able to run less duty cycle and smooth out the injection table not to mention he now requires less throttle pump.

Ruthr33 Enthusiast

Ruthr33

Posted
Posted

Hijack, I have fpr800, seems to work ok.

The only thing that bugs me I'm not allowed to touch the throttle when the car is dead cold for the first minit or it will stall. If I increase the throttle pump will that affect the tune when it's warm or is there a seperate cold pump

89CAL Grand Master

89CAL

Posted
Posted

Hijack, I have fpr800, seems to work ok.

The only thing that bugs me I'm not allowed to touch the throttle when the car is dead cold for the first minit or it will stall. If I increase the throttle pump will that affect the tune when it's warm or is there a seperate cold pump

Wut?

Are you sure your cold start is tuned 100%? Depending on the ECU, may need some fuel corrections changed or even timing

I doubt the fuel reg is causing issues when cold but not when hot.

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

Hijack, I have fpr800, seems to work ok.

The only thing that bugs me I'm not allowed to touch the throttle when the car is dead cold for the first minit or it will stall. If I increase the throttle pump will that affect the tune when it's warm or is there a seperate cold pump

what ECU?

what you can do is use the temperature fuel compensation and add in more fuel when the motor is cold.

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

Yea go turbosmart my genuine tomei one causeing me issues had to go to turbosmart

and now you fry tyres for days :)

I've converted you hahaha, preach the good words to the masses!

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