FPR question

[NICO]

i have a question about the factory fuel pressure regulator, if i punch in the top of the regulator a little would i get more gas out of my injectors?

[-K-]

Maybe, I know it is done to some but I don't know if ours can hold up to it.
What about the SVX FPR I hear about?
I'm going to make a dirt cheap JY adjustable FPR, stay tuned.

[vrg3]

Yes. If you crush the top in a little, you increase the tension on the spring, and so increase fuel pressure and therefore injector flow.

To make it adjustable, all you have to do is make it so you can vary the tension on the spring. Our FPRs are tiny so it'd be hard to do this to ours, but it's supposedly easy on the Bosch ones that are used by a lot of European cars.

The SVX uses the same fuel pressure as our cars.

[NICO]

ok good becuse i crushed it a little bit. i should welled a nut and put a bolt in a extra one i got and test it out.

[biggreen96]

nico- how much did crushing it a little bit increase the pressure?

[NICO]

to tell you the truth i dont no, becuse i didnt get to hook up a gauge. but i am going to crush it agian a little bit more with a gauge, becuse i had to put my factory injectors in and take the sti ones out. the car does not want to run right with the sti injectors in, i had to swap my legacy turbo into a impreza and made my intercooler smaller and it screwed up my hole set up. but i will let you no the psi before and after i do it.

[biggreen96]

ok cool

[LaureltheQueen]

why not use a tunable fuel pressure regulator? Do they cost that much extra?

[Legacy777]

why not use a tunable fuel pressure regulator? Do they cost that much extra?

With how are fuel system is setup, it doesn't leave much room for a tunable fpr without redoing things. However if you want to ghetto garage it, simply disconnect the vacuum line from the stock fpr, add a tunable fpr in the line coming from the filter going to the fuel lines. You'd also need to tap into the return line as well.

[NICO]

another question what if i just unpluged the vacum line in the fpr line and left it unpluged, would that run the injectors full out or would it not be good to do this.

back to factory this is killing me, can wiat till my greddy e-maneg comes in. then i will be ok with running the sti injectors.

this past sunday i had a crazy meet with the toronto-subaru-club, there is a guy that lives in my city with a 11 sec subaru MY GOD how fast it was, the turbo on it makes my turbo looks like a playschool kid. 22psi 750cc ecutec an i think type-c motor or somethink in those lines, GREAT BALLS OF FIRE.

[THAWA]

I thought you used to make 350 whp? Why are you so impressed with his car?

[vrg3]

Don't unplug the vacuum line. There's no good reason for it. On a turbo car it'll actually reduce fueling on boost anyway. And even if you're using an aftermarket FPR, you don't want the stock FPR raising fuel pressures at low loads.

[NICO]

becuse he s got 498 at the wheels, i can hang with all the big boys and there horse power monsters. shaveing 800lbs out of my legacy-turbo in a impreza has made me one fast car. got a smaller intercooler now so i think i lost 25hp so 325hp is good for me right now, i got some tricks in my sleeves if they would hurry up and send them to me.

it looks like i need a bigger turbo from my view an a little tuning.

thanks vrg3 its only to get me bye for a couple of weeks. then the tuning comes in to place

[-K-]

If you put an adjustable FPR in it would go in the returne line.