Fuel Pressure Regulator.

rushy

There's quite a few posts popping up on vectra c about fuel pressure regulators for the 2.2, have tried telling them to pop in over here but they don't seem to be posting. So whats the score, is it a doable mod, does it give you anything else on a pretty stock lump? There not listed on the site for the z22se on the FSE site. Also from what I know the z22yh runs a higher pressure so could putting a yh reg on a se give you something extra?

vocky

the standard fpr is a 4 bar unit 8)

if you alter the pressure the ecu adjusts the duration of the injector pulse, so you end up with exactly the same amount of fuel :roll:

the best way to get more fuel is a remap dunno..

rushy

You know I had a feeling it was going to do something like that. Its not something I'm after, but there seems to be a rebirth of the z22se on vec c, must be loads coming on the market now warranty's have run out.

coljnr

vocky said:
the standard fpr is a 4 bar unit 8)

if you alter the pressure the ecu adjusts the duration of the injector pulse, so you end up with exactly the same amount of fuel :roll:

the best way to get more fuel is a remap dunno..

vocky so if you turn increase the pressure by 0.7- 1 bar of pressure on a slightly modded car the ecu wil cancel it out? what the point int those fse fuel regulators then?

rushy

They only seam to be listed on older lumps where the ecu controls and monitors less things.

coljnr

rushy said:
They only seam to be listed on older lumps where the ecu controls and monitors less things.

ye seen the fse regs on the older ones but not the new lumps, thats y i bought adjustable, o well just save it for another car one day

markv

The ECU on the z22se uses static fuel pressure. Other engines use fuel pressure dependand on the vacuum in the inlet manifold. Both strategies require different mapping of the ecu.

Mark

JohnnyN

pxc150 is running a FSE Boost valve on her SRi150. I was under the impression that it would make no difference?

notsure.gif

Madmancunian

Sounds like a waste of time then ???? :cry:

boothy2_2

i thought it took the pressure from the manifold area, and moving it to below the throttle body gave it a constant 4 bar pressure notsure.gif

markv

Pressure is just below 4 bars when the regulator is connected to atmosferic. When you apply vacuum to it, it drops to 3.2 or thereabout.

Mark

Lightning_Coupe

markv said:
Pressure is just below 4 bars when the regulator is connected to atmosferic. When you apply vacuum to it, it drops to 3.2 or thereabout.

Mark

So would it be better to leave the fpr disconected to atmosphere and always have 4 bar then? Because conected to the intake manifold it must be always under vacume and therefore less than 4 bar pressure?

I'm confused?? I thought Vocky did this with a digital presure gauge and proved it best conected to the Intake manifold? Are you sure you have it the right way round mark? dunno..

JohnnyN

The pressure at atmospheric is low, that's why it was found to be better pressure at the intake manifold.

;-)

vocky

the reasoning behind the fpr mod is...

the standard set up has no suction at tickover and suction at higher revs

a modified inlet system provides NO suction at all

the fpr mod simply provides suction all the time

whether it raises the fuel pressure or lowers it doesn't matter, it's doing what GM designed it to do, have suction at higher revs.

Lightning_Coupe

well it makes more sence to me to have a lower pressure at idle when there is little vacume, that way it gives a slightly more finite adjustment of the injector pulse to achive the optimum or at least most economic air fuel ratio. Increased revs and hence greater intake duct vacume I would have thought should result in a greater fuel pressure to chuck the fuel in when its needed. I absolutly cannot see it being the other way around but I dont mind being educated further if Im wrong.

Now on to an intresting note..... If your car runs a little lean with all the intake and camshaft mods weve been doing, and it sounds like its a genuine issue for those that are at this stage, an alternative to bigger injectors would be to increase the fuel pressure right? But That means an FSI boost valve or something right, which is slightly off putting because of the cost and setup.

What If I told you I know the part number for a higher pressure GM fuel reglator thats a direct replacment for the standard one. Two little screws on the end of the fuel rail and its swapped out. If anyones got an EPC catolouge they can check this out for me but Ive had it from a good source and Ive seen it in use. I forget what its off i'm sory but Ill enquire again tomorrow and try to find out a little more detail. The Part Number is 93176029. Again, if you can dig any info on it up out the EPC that would be great, and also, if I'm completely wrong, please re-educate me, your never to wise or old to learn a little more as far as im concerned.

vocky

if the engine is running lean the ecu will allow a higher fuel pressure, as it wants more fuel for it's injectors dunno..