Recomend Me An Adjustable Fuel Regulator

[vern 0]

As title really, when setting my TT on rolling road the injectors were about 95% duty. Am I right in assuming that if the fuel pressure is raised, it will reduce the injector duty, if accompanied with fueling changes.

I have seen an FSE 1-1 adjustable regulator on the bay of E for £57 delivered. Are these are up to the job or are there any other better makes.

[saveloy 8]

Since your engine is turbocharged, when on boost the regulator will not supply the extra fuel, as in a N/A engine. Positive pressure causes the regulator to act in an inverse manner. So, the only way to increase your fuel level is to increase it at the 5th injector.

If you open up the box you will find a couple of pots. One sets the start pressure for the injector. The other sets the level/duration. It is this one you need to adjust. It may give you the increase in fuelling you seek.

[vern 0]

Should have said I am running Emerald with larger injectors.

What is controlling my fuel pressure at the moment then if the stock regulator is inversed when on boost??. Should I have changed the stock regulator when fitting the turbo to the engine.

Edited October 3, 2007 by vern

[welshpug 1,657]

IIRC a system like emerald needs a static fuel pressure like later pug engines have.

 

it just opens the injectors for longer or puslses them more if the MAP sensor gives a positive reading.

Edited October 3, 2007 by welshpug

[vern 0]

what recommendations did I get in this thread, as posts have been lost.

[Sandy 191]

My preference is to use one of the later fuel rails that fits the bosch capsule regulators. A wide range of pressures are available, they are reliable and easily changed.

[vern 0]

When you say later engines mine is a 1991/2 1.9, where can I get the differing pressure values capsules from, the only place I have seen them, they have been over £80.

[welshpug 1,657]

later engines have the pressure regulator in the centre of the rail, like on the 2.0 Mi16 and gti6, many other XU's share the same setup, but I think from what sandy said the injector spacing is the same as well as the size of the injectors

[Sandy 191]

I'd assumed we were talking 16v, sorry!

[vern 0]

I still need to try and raise the fuel pressure, so has anyone else got any ideas??.

[Sandy 191]

Sierra Cosworths and Cavalier SRis etc use an external hose talied regulator you could put in the return line to increase the pressure.

[vern 0]

Have done some investigating on the fuel regulator.

 

Bear with me and correct me if I am wrong.

 

As said by Savloy the fuel pressure will tail off as boost rises with the stock regulator. So in my car the engine has been set up with the stock regulator. Replacing it with a static one, I will need the engine setting up again as the engine has been set up to overcome the tail off in fuel pressure, so if just change it for a static regulator, with no fueling mods I will overfuel at the top end.

Have been looking at suitable adjustable regulators turbosmart seems to get good reviews, anybody with any experience of these?.

[saveloy 8]

Vern, you are running programmable management. The ECU can't supply the extra juice, since the injectors aren't up to the job. What are you using, injector wise?

Forget the regulator, it is a waste of your time. It will not do a damn thing. So stop messing about.

You need a set of larger capacity injectors. Rover 220 Turbo items, or Volvo T5 ones are good.

The Emerald should allow you to scale the new injectors, so you won't need to adjust the map at all.

[rallyman 0]

Sounds like a big power set up, basically you need to either run bigger injectors which would allow more fuel out - preferable OR go for a remap that will allow you to cater for the "tail off".

Do you have a lamda sensor on it and are you running closed loop? if so the ecu "should" adjust though if it is running "off a map" then it may go rich but couldnt you just do this and just scale it?

[vern 0]

Sorry have only just seen your replys savloy and rally man.

 

To answer savloys points, I am already running larger 330cc injectors, but these are maxing out (95 - 100%) at the upper rev range, As prievously said, I could improve this as fuel pressure drops as turbo comes on boost and revs raise, as I am using stock vacum regulator.

 

Rallyman I am using closed loop wideband lambda. The car has been already mapped with the tail off, I am just tring to lower the duty of the injectors.

 

As far as I understand, raising the fuel pressure, will decrease the injector duty rate, as more fuel is allowed through the injector for the same opening duration????. To raise the fuel pressure I need to change the regulator, and doing so If I get the corect one I will remove the tail off of the standard regulator.

[Normski 1]

Vern, you are right. Raising the base fuel pressure will allow the injectors to run at a lower duty cycle.

 

Is your current regulator not manifold pressure referenced? In which case it will raise the fuel rail pressure as the boost increases? Is your fuel pump capable of supplying enough fuel to maintain the pressure you want?

 

For my Scooby, I have a Fuel Lab adjustable regulator. It's a quality bit of kit, machined from billet and anodized. But it was ~£150 It can be run referenced or not.

[vern 0]

Thanks for reply normski.

 

The regulator I am using at the moment is the standard one, it is referenced from the inlet manifold but works on a vacum, but now it is turboed it is putting boost through the regulator making it work in reverse ie lowering pressure. I have got uprated fuel pump already so should be able to raise the base pressure a bit.

£150 is a bit steep have been looking at a 1-1 adjustable regulator which operates off a vaccum or pressure for about £50 - £60.

[Normski 1]

Is there two types of regulator?

 

Because the way I've read they work is the opposite to the way you just said. I.e. when at idle for example, there will be high vacuum in the inlet manifold so when the injectors open more fuel than required would be pulled through. Being manifold pressure referenced, at idle the fuel pressure would be reduced to compensate.

Conversly, with boost in the inlet manifold, not enough fuel would come out. And so the fuel pressure is increased.

 

In both cases the fuel pressure is held at a constant value as 'seen' by the injector.

[vern 0]

What you have said is correct for a standard regulator, but how I understand it, as I have converted to turbo power the boost upsets the way the regulator works?