DO I NEED AN ADJUSTABLE FPR??
 

Yes I've searched. Yes if I get one it will be AEM

So I have a turbo b18c5, it has a walbro 255, Delphi 525cc injectors,stock fuel rail. I'll be somewhere around 400hp

Now I read you need one on anything bigger then a 190lph pump to keep your pressure lower but I have a feeling my injectors are going to be pretty much maxed, so the psi might need to be higher anyways?

TIA

Re: DO I NEED AN ADJUSTABLE FPR??
 

cant hurt

Re: DO I NEED AN ADJUSTABLE FPR??
 

No, you need to take the car to a tuner. 525CC injectors should be able to flow enough to handle up to 450whp, and any competent tuner can set it all up to work correctly for you. Don't waste your money on an FPR.

Re: DO I NEED AN ADJUSTABLE FPR??
 

I know that:) but do I NEED it?

Re: DO I NEED AN ADJUSTABLE FPR??
 

Yes it will be getting tuned when I get the motor finished and running. Just wasnt sure if it was something that was needed for my setup with walbro 255 and stock fpr

Re: DO I NEED AN ADJUSTABLE FPR??
 

I would get one. It keeps a linear fuel pressure curve 100% reliably which means no random funny business down the road. For 100$ now you could save your whole setup someday.

Re: DO I NEED AN ADJUSTABLE FPR??
 

Ask your tuner. I've been running DSM 480's on my turbo setup, 255, and completely stock everything else with zero problems. I doubt you'll need one.

Re: DO I NEED AN ADJUSTABLE FPR??
 

how much power are you making?

Re: DO I NEED AN ADJUSTABLE FPR??
 

Currently, a hair under 230. I've been talking to my tuner about my current build-in-progress, and he agreed that I won't need an adjustable FPR for the 500WHP I'll be making on the street, or the 700 goal on my track tune.

Is it useful? Hell yes it is. Is it needed? No.

Re: DO I NEED AN ADJUSTABLE FPR??
 

Thanks guys

Re: DO I NEED AN ADJUSTABLE FPR??
 

Your definitely gonna need bigger injectors or you are gonna have to crank up the fuel pressure for 500 whp. It's recomended to upgrade the fuel rail at that level. You'll be seeing over 100psi of fuel pressure with those injectors.


500hp x .60 B.S.F.C. = 300

4 inj. x .80 duty cycle = 3.2

300 / 3.2 = 94

94 x 10.50 = 987cc

Re: DO I NEED AN ADJUSTABLE FPR??
 

I said around 400hp my injectors should be good might have to turn the psi some though depending on when I want to stop making more power, most likely like I said it will be once I hit 400 hp cuz it will be a dd. I'm not going to upgrade the fuel rail I'm just wondering if I'm going to need the fpr

Re: DO I NEED AN ADJUSTABLE FPR??
 

yes i would say you need it

Re: DO I NEED AN ADJUSTABLE FPR??
 

Well 400hp equates to over 700cc and how are you going to increase the fuel pressure without a FPR?

Re: DO I NEED AN ADJUSTABLE FPR??
 

Get one. Get 750cc injectors for room to grow. Better to have injectors that can take whatever your throw at it and not be anywhere near full duty. But i'd keep it to 300hp on the street. 350 max.

Re: DO I NEED AN ADJUSTABLE FPR??
 

This is what I figured and why I posted a thread asking
I know I need bigger injectors for room to grow I was going to get id1000s but I don't have money for them right now and those injectors should be enough for the power I'm going for, yes I know everyone says you'll want to turn it up later but that won't be for awhile my goal is more then enough for a DD. Plus my Hondata s300v2 is already set up for my injectors.

And my real goal is high 300s low 400s. I didn't put all this money into this build to only make 300hp:P which we all know coulve been done stock.

So again guys, I will need it for sure correct?

Thanks again for the response

Re: DO I NEED AN ADJUSTABLE FPR??
 

500 crank hp x .15 = 75

500 - 75 = 425whp roughly

400 crank hp x .15 = 60

400 - 60 = 340whp roughly

300 crank hp x .15 = 45

300 - 45 = 255whp roughly



500 crank hp x .60 B.S.F.C. = 300

4 inj. x .80 duty cycle = 3.2

300 / 3.2 = 94

94 x 10.50 = 987cc

Re: DO I NEED AN ADJUSTABLE FPR??
 

OEM fuel rail, FPR and lines are good for up 500whp with needing to upgrade. So the stock FPR will be fine no need to upgrade it.
ID 1000cc injectors for the win, all the injector you will need unless going to E85 or super crazy power.

Re: DO I NEED AN ADJUSTABLE FPR??
 

Yeah, this is only true if the injectors are 1000cc. He does not have 1000cc injectors. He has 525cc injectors. Which means he has to increase fuel pressure and up the duty cycle of his injectors. NOT recomended.

43.5psi fuel pressure 1:1
fuel flow needed 1000cc/min
injector size 1000cc/min

160psi fuel pressure 1:1
fuel flow needed 1000cc/min
injector size 525cc/min