72 replies to this topic

[CRUISN]

In all honesty CRUISN, if you think it looks the goods, and don't mind the ride quality, then who gives a rats arse what others think..... You ain't retarded

Thanks Jeff.

I was just messing around though.

To be honest im not rapped in the height or the ride, but thats an issue for later on down the track.

[Jeff]

So..... Who can give me some advice about parallel fuel rails and fuel pressure regulators. I want to solve this leaning out issue I seem to be getting at high RPM. I can only assume its because of the factory fuel setup. I don't want to do a backyad DIY job as I'm not confident in doing the work. What rails should i be looking at, setups should i be looking at, Fuel pressure regulators should i be looking at..... or rather not looking at. I think i remember reading somewhere that Turbosmart FPRs are shit, any others i should steer clear of. Thanx in advance

[Soop]

Have your Injectors reached maximum duty mate?
What fuel pump are you running?

Have a squiz at this thread it includes some detailed information on the parallel setup:
http://www.subyclub....hp?showtopic=82

Pressure regulator here:
http://www.nengun.co...ator-8mm-nipple

Though i doubt this will be needed.

Wide band 02 Sensor and digital gauge here:
http://www.innovatem...roducts/MTS.php

To see how much it is actually leaning out.

Fuel rails themselves will be fine. If the injectors have reached maximum duty perhaps look at some 440cc or 540cc injectors.
If its the fuel pump, look into a Walbro (someone will be able to confirm the part number) or a Bosch044 if they make them to suit the B4 tank.

What other details can you give?
What boost pressures are you running?
Are you sure that it is actually leaning out?

[Jeff]

Thanx Soop I've already put in a 255lph walbro fuel pump about a year ago, and I'm certain the Aus delivered B4's had 550cc sti injectors standard. The duty rate is higher then what i would like it to be for the tune I just thought that the standard subaru fuel setup was shit and want don't want to kill the engine when I'm testing/tuning. Thats the impression i get when i read everything about the setup anyway.

[Kosti]

Hey ya Jeff, no need to thank me champ! Looking good champ and can't wait to see you on the track!

[Jeff]

Thanx Kosti, did you get my email about the FMIC??? I sent it a while back. Sorry about the brackets hey, if you still need them when I've finally got the cooler on, they're yours.

[Kosti]

Thanx Kosti, did you get my email about the FMIC???

I sent it a while back. Sorry about the brackets hey, if you still need them when I've finally got the cooler on, they're yours.

yeah, thanks, did u get the pictures I sent you for the pluming, what did u think of them?

no sweat, when ever your ready I'll grab them off ya

[Jeff]

Yeah, are the pics from Shauns car??? they look familiar. I've got the Weekend off so i might get me head in there and see if i can see some possible routes for the pipework between working on the grill and other tasks at hand

[Soop]

Do they really have 540's? I find that hard to believe. 380's - 440's maybe. As i said, look at Lance's thread that i Linked to. It contains information on how to setup a parallel fuel system. In standard form (On the older generations anyway) cylinder #2 tends to lean out at high RPM. Changing to parallel rails obviously make sure that the injectors are all getting equal amounts of fuel. This stops the cylinder leaning out. As i said, make sure that it is actually leaning out. Also if you can, check what the knock sensor is doing. If its trying to pull timing either you have too much ignition advance or not enough fuel or both.

[Jeff]

its not pulling timing and the knock sensor isn't picking up anything, but there are some inconsistent AFR readings under high load/rpm and it is audible above 6000rpm so at the moment it doesn't get driven above 5000rpm. Kosti can you confrim the injectors on our car??? 550cc???

[Soop]

What is the injector duty at, at the moment?

[Jeff]

nothing..... its sitting in the garage...lol seriously, its only 65% at the moment but I've detuned it for the time being. I've had it at 110% once before i detuned it, that's calculated off 500cc injectors. Edit: its actually 65% at the moment while detuned not 75%

[Soop]

That could be a real good reason for it leaning out. I'd be PMing Kosti to find out what size the injectors actually are.

[Jeff]

thats what the factory rom image states they are also, So I'm pretty sure that that's whats in there. They wouldn't have the wrong thing from the factory.

[Soop]

I'm not disputing it, as i know no different. I've been told that its a good idea to start considering new injectors when they hit around 90% duty. So that would be my first port of call. It doesn't matter what else you change on the rest of the fuel system, if the injectors cant physically flow enough fuel to meet your needs. Sard 650's ftw?

[Jeff]

Yeah, but thats only off 1 injector, with the fuel setup the way it is, how do i know that all the injectors are getting the same amount of fuel pressure. Thats why i want to do this first as i don't want to get bigger injectors if i really don't need to. The amount of pressure drop in the fuel system at that sort of RPM and Pressure could be a lot

[Soop]

If that's your fear, then investigate the parallel fuel rail setup. Its pretty cheap and fairly simple to do.

[Jeff]

Question..... Will fuel rails designed for a wrx fit the B4??? I can find heaps for the wrx ej20 2002+

[Soop]

You don't actually need to change the rails themselves.




It's all in the hoses underneath the manifold.



This setup ensures that all the Injectors receive the same pressure.

[Jeff]

Thanx Soop, Still interested to know if they will fit? I might employ this setup to test it out and see if this solves my problem. If it does I'll prolly end up buying some new rails anyway.