Fuel Pressure Regulator Question

[WACR]

After quite a break from working on my car, I am now back into it. I know there have been several threads regarding the fuel pressure regulator set up for the LS1 which now runs a single feed line to the fuel rails as standard. Am I correct in thinking that this little device shown between the two fuel rails is a standard regulator? The workshop manual I have says it is. If so, I am confused since I have read some postings which indicate the standard LS1 setup has a in-tank fuel pump / regulator, not sure what this little thing is doing on the fuel rail then.
Do I need an after market regulator then?
If anyone can shed any light on this it would really help.

Cheers

Richard

[sambo]

I thought the new single line fuel pumps contained a surge pot and regulator internally? I haven't pulled mine apart yet but that's my understanding. See my gallery for the VZ Crewman pump fitted to my fuel tank.

[WACR]

Thats what I am lead to believe from all the previous posts on this topic, its just this little device in the picture has me puzzled. It may serve some other purpose?

[sambo]

Sorry I don't have my engine yet and I haven't played much with these new LS Chevs. Perhaps have a look over at LS1 forums: http://www.ls1.com.au/forum/?

[WACR]

Thanks for that, I will have a search and let you know if I find anything.

[alffie]

The LS1LS2LS7 have the pump, reg,assy in the tank so it reduces the evaprotive emissions. Thats why the VTs got vapour lock and Holden went to the two covers instead of the turtle shell. On the LS7 the thing that looks like a reg is the purge valve for the charcol canister

[alffie]

The LS7 is slightly differnt with the breather/charcol set up because of the oil tank breather set up. There are rails around that are set up like the Holden V8 to return back to the tank and keep the fuel cooler.

[alffie]

I just got an aeromotive reg and a Bosch 023 intank pump with the VS tank. I have to pass evaprotive emsissions as well. Which means useing the complete charcol set up out of a post 93 car

[WACR]

Alffie, so this thing is the purge valve for the charcoal cannister?

[Aussie Mike]

That little piece on the fuel rails in your pic is actually a damper. It's a spring loaded reservoir that takes some of the surge out of the fuel system as demands increase and decrease. Because the regulator is right back in the tank on the stock setup it's sometimes not as responsive as a regulator right up near the rails. The damper fills in the holes.

The carbon canister purge valve is actually a black plastic solenoid valve about 1.5" in diameter and about 3" long that's cliped to the manifold just below the fuel rails. There's a couple of wires running to it and it's locked off when the engine is not running. Once it fires up it will let the engine vaccum suck the fuel vapours out of the carbon canister.

There are plenty of options open for pressure reg setups. You can run the factory in tank pump setup cut down and installed in the top of your tank. You could also use an after market reg back at the tank and plumb it in the same configuration as the factory setup. This is probably the easiest way as you will only need one fuel line up to the motor.

Alternatively you can run a feed line and a return line up to the engine bay and install the reg in the engine bay. This could be connected via a single line from the reg to the factory rails. Most after market regs have 2 ports on the high pressure side. One is usually used for a guage but it could be used to connect to the rails instead. I've gone one step further and used after market rails and have cool fuel constantly circulating through them with an inlet and an outlet on the rails.

I've got some schematics for different fuel systems I drew up a while back. I'll see if I can find them and post them up.

Cheers

[WACR]

Thanks Mike, thats cleared that one up which is a great help. If you were to go with the easiest option of mounting an aftermarket regulator back at the tank, where is the best location on the Classic Revival to mount it both to keep it out of the way and for access to adjust etc?

Cheers

[sambo]

So what you're saying Mike, is that even with the single line in-tank pump from the factory, there's also a separate regulator required somewhere down at the tank? I'm yet to check out the VZ factory setup in a car so excuse my ignorance!

[boxhead]

If your using the factory pump then you will see there are 3 outlets on it.
The 2 outer ones are marked F & R.
The F is the feed line, the fuel is pumped out of this pipe and to the filter, the filter has a "T" piece hose conection, fuel is fed into one terminal on the T piece and flows out the other 2.
The T piece is connected to the fuel filter and the 3rd terminal goes back and connects to the "R" terminal on the pump, this is Return.
The regulator is built inside the pump assy in the "R" pipe end.

The centre pipe is for the vapour canister line.

[sambo]

Ok, the pic below is from my gallery. What am I missing, apart from the obvious fuel line to the engine, currently capped off on the top of the pump. Thanks.

[boxhead]

Your fuel pump is different to mine Sambo.

Mine has 3 outlets at the top.
It looks to me like the T piece I am refering to is built inside your pump assy, so there is no need for it outside the tank.

[sideshow]

they usually all have 3 lines


middle one is charcoal canister vent

the pip ethat uis snapped on yours is either return or feed

either try to screw a pipe onto the broken bit or buy a new pump

i personally would buy a new pump

60 psi of fuel pressure is probably not a good thing to have a pipe break and fuel go everywhere

about 1 in every 5 2nd hand fuel pump assemblies i work on have broken bits

then u have to make sure u get the corect fuel gauge to match the feul level sender in the hiolden pump assembly

another prob is holden changed the reistance values half way thru vy pumps depending if hsv or monaro or std

most guys who i wire up fuel level gauges always get the wrong type

[sambo]

Mine's a brand new, unused VZ Crewman pump and nothing's broken mate. I think the only thing missing is a lump of alloy with 6.0L bored out of it.

[sideshow]

ok vz has a diff resitance to vy for fuel level sensor

so if your goin to get gauges then give them the fuel pump assembly to get the correct gaues to suit the sender

or your fuel gauge will do some weird asssssssssssss poo

hehehe

[sambo]

Ah... thanks sideshow. Now I can see why Mike went for mechanical gauges.

[sideshow]

VY – Fuel Gauge VZ – Fuel Gauge
40 ohms Empty 250 ohms Empty
250 ohms Full 40 ohms Full


fuel gauges are never mechanical in this day of age