Fuel Reg

[ryan101]

i have a stock rb25det with big fuel pump, fmic, exhaust running 11 psi wat should i adjust my fuel reg to? if i adjust to high the idle plays up, it was on 30 kpa now its on 25kpa idles beutifully?? any thoughts?? is that too low?? was 30 too high??

thanks

Edited January 11, 2010 by ryan101

[R31Nismoid]

You mean to say you have one that is adjustable?

I gotta ask... why?

The factory one is fine for just about every application sub 450rwkw.

24psi base, is to low either way.

[MrStabby]

Adjusting the fuel pressure away from the standard level means you'll have to retune, as you are effectively changing the flowrate of the injectors (a little). You don't mention you have a programmable ECU so set it to the stock level. But as Nismoid stated you dont need it so why not put the stocker back on and sell the adjustable. One less problem plus money

[~Nvied~]

that seems to be a bit low. Mine sits at 3 bar all the time. I did before my tune had it resting at 24psi which i was told by the whole world was way too low. So i increased it and blew my spark plugs because increasing made it run too rich. I think you should keep the adjustable one as you modify later on for bigger power you can adjust it accuratley.

For now either you can chuck you old one back on or save up and go to a tuner and get it tuned to run at 3 bar fuel pressure. You cant just put the pressure up without tuning the engine to run at it.

[R31Nismoid]

that seems to be a bit low. Mine sits at 3 bar all the time. I did before my tune had it resting at 24psi which i was told by the whole world was way too low. So i increased it and blew my spark plugs because increasing made it run too rich.

umm... that is what a skyline does on the factory ECU - runs super rich...

I think you should keep the adjustable one as you modify later on for bigger power you can adjust it accuratley.

If you purchase the correct injector size for the application, the factory Fuel Reg is good for over 400rwkw.

I've made 370rwkw - and i can think of another 20-30 odd people who've made more than that with the factory fuel reg.

And then the 100's upon 1,000's who've made less and are still perfectly fine.

Fact still remains - you do not need one.

[winstonusmc]

You set the pressure with the vacuum line removed to 3 bar or 43psi. When you reattach the vacuum line, it should dip down so that its 3 bar minus manifold vacuum. Mine sits around 2.65bar at 500mmHG with an aeromotive FPR and an RB26 @ 950rpm idle.

[JonnoHR31]

25-30kpa is around 4-5psi, i doubt the car would even run with that little pressure. as said 3 bar or 43psi is what it should be. if the stocker works put it back in, only reason to go aftermarket is if you break standard ones

[ryan101]

it was on 3 bar but it idled and stalled all the time and when i dropped it to 2.5 it didn't stall and idled fine??

i don't have the stock 1 the car neva came with it

mayb i will turn it up a lil more mayb 2.8 see how that goes

[Roy]

If you purchase the correct injector size for the application, the factory Fuel Reg is good for over 400rwkw.

I've made 370rwkw - and i can think of another 20-30 odd people who've made more than that with the factory fuel reg.

And then the 100's upon 1,000's who've made less and are still perfectly fine.

So some extra pressure behind the injectors doesnt help spray patterns or fuel atomisation?????

[R31Nismoid]

Well you have to ask what the injectors are designed for.

If they are designed for the factory pressure, then no you don't.

I beleive bosch require extra pressure or some other brand, but then i wouldn't call them correctly suited as they are a generic style injector

I agree with what you are saying though - just not in this particular application of it.

[ryan101]

im sorry i should have explaind wat i meant a lil better, at idle the fuel reg was on 30-32 psi, i have now adjusted it to 28-29 psi that is while it is idling!! but when i hit the acclerater it goes up to 45psi at bout 4000revs and no more stalling when i brake,

[R31Nismoid]

^ umm... ye that is how the reg works.

It rises in accordance with boost.

Do you have a ATMO BOV?

[PM-R33]

Sell reg, buy a stock one, put it back on. No more problems ever.

Use remaining money on sold reg for booze, strippers or furthur car modifications.

Simple really.

[ryan101]

it is the stock BOV not to atmo!!

where can i buy a stock 1 from? (fuel reg)