4AGZE fueling, idle and TB upgrades

[Drifty Midship]

Next phase in my build up is to re-do the fuel system.
Just would like to hear what other 4AGZE owners on here have done in this area.
I'm talking everything from tank to cylinder.
Planning to keep the stock fuel rail and intake mani but everything else that bolts onto it
I am happy to swap... and I really wanna piss off the factory ISCV and go with something else if possible.
I've got a fresh engine, 7mgte Injectors and an adaptronic but need to know what other parts to collect to bulletproof/futureproof the system before it all goes in.

So seeking opinions/advice on...

Fuel pumps
Pulsation damper
Fuel pressure reg.
Throttle Body (any upgrades that fit)
ISCV - Alternates and how to bypass the OEM one if using the stock TB
Any other ideas or tricks?

Cheers

[beauy]

Hey man, my 4agze which is a converted to Turbo and is in a 86. Im running -6 braided line (in and return lines) from fuel rail to fuel system/tank.

I have a 2litre serge tank, two large pumps (work as out of tank and into serge and 2nd is out of serge and into engine) I also have a resignator and custom pick up in the tank.

Mines a bit over kill but in areas like fuel, cooling and braking i dont think you can ever go to over board.

Later on my stock tank will be coming out for a custom fuel cell.

I hope that was the sort of ideas you were looking for.

(p.s i didnt say brands and models of pumps as i think you should decide what pumps you want to use for your application with out being clouded by a slightly different set up that wouldnt be exactly the same as yours)

[Duk]

You are staying with a supercharger?
I've got a 4AGE TB (with blocked ISCV) that has been bored out to 60mm and it bolts onto the factory cast pipe but the pipe needs to be ported heaps, especially at the TB flange. Having said that, the cast pipe (probably) can't be taken out to 60mm all the way thru, so it tapers from 60mm at the flange. It worked out that the 60mm bore offset the 10mm TB shaft quite well for a 55mm pipe (from memory).
Ultimately there are too many bends of too small a radius in the whole TB to SC (270* from TB to SC inlet), so if you could remove some of the bends then the inlet will flow much better.
Wasn't Adsport doing something like this on his AW11?
My 60mm TB (I'm not actually using it, I just added a turbo instead ) had the ISCV ports bogged up with some sort of hard epoxy like JB weld.

[Hen]

Fuel system I've used for a 110rwkw 4AGZE in an AE86:
- Holley blue lift pump (total overkill and stops working regularly)
- Cheapo plastic fuel filter
- 0.7litre surge tank
- VL EFI pump
- EFI fuel filter
- Stock pulsation dampener
- Stock rail
- Stock injectors
- Stock FPR
- All fuel lines were the stock 6mm ones.
Aside from the Holley that worked fine for 4 years.

Then when I built up to 140rwkw (optimistic reading I feel) I only changed to 8mm fuel feed line, pissed off the pulsation dampener and fitted 7MGTE 440s. I have driven it very little, but also seems to work.

As for ISCV, you can just remove it and plate it off. I did this for a while before I got my aftermarket ECU to control it properly. You could also make up a plate which fed off to whichever type of ISCV you choose (XF Falcon ones get mentioned). Once you pull the stock one off it's obvious how it all works. The only thing is, tuning idle on a 4AGZE with aftermarket ECU is hard, given the big post-SC volume, especially with a bigger intercooler. It can be done, but usually you end up with a highish idle and slow response.

Hen

[Drifty Midship]

Can anyone tell me the stock fuel pressure of 7MGTE ?
Basically, with the bigger injectors will I need to upgrade the fuel pump or change the FPR?
Will having bigger injectors decrease the pressure in the rail? (sort of thinking it will)
I haven't tested pressure at the rail yet so I guess this is the next thing I should do to make sure the 20 year old pump and regulator are both still up to scratch...
If the 7MGTE stock pressure is the same as the 4AGZE then i'm assuming the flow will be correct and I wont need to stuff around with hi-volume pumps or regulators...?
Whats with the rising rate regulators? is it worth putting one of these down from the stock FPR?
Does anyone know the functionality of the VSV that goes to the FPR? What is does, how it is switched? This will get deleted when the adaptronic goes in and will run direct of man pressure.
4AGZE pressure is 33-40psi, 4AGE pressure 38-44psi. ????
Apologies for all the questions trying to get a grip of this stuff it's an it's a pretty new area for me.

[Hen]

Sort of answering your questions backwards...
Yes, 4AGE runs slightly higher fuel pressure than ZE, not sure why. With the stock ECU you need the stock injectors and FPR. With an aftermarket ECU you can choose what you like as you can tune to suit them.

The VSV going to the FPR allows the factory ECU to lift the fuel pressure slightly (I think) when it sees fit. Again not needed if you are running an aftermarket ECU.

The factory FPR is reliable and unless you are going really silly (250+rwkw) I'd stick with it. Rising rate regulators are only required if you are turboing an NA car and want a cheap, questionably reliable way to increase fuel going into the motor on boost. Also only use one FPR in the system, two is a total waste of time.

Bigger injectors will not decrease the fuel rail pressure. The rail pressure will only drop if the injectors are using more fuel than the pump can supply. This is a bad sign and means things will run lean.

You can upgrade injectors and leave your stock FPR. Your pump must be able to supply enough fuel for the engine at the rail pressure you will be running (fuel pump flows drop off as you increase the rail pressure). So decide what power you are aiming for, work out how much fuel that requires, choose suitable injectors and then a suitable pump.

Hen

(Yes, I have generalised somewhat here, but the basics hold.)

[TERRA Operative]

If you want a larger throttle body on the GZE setup, go get a 3SGTE throttle body. It's bigger than the GZE (same size as the 4AGE) and will allow you to retain the idle control.
I've done this on my car and I love it.

Why do you want to get rid of the factory ISCV?

I've also got HKS adjustable cam gears (retarded exhaust by 3 degrees), a Sard FPR, bigport cams, Apex'i pod filter and 20V Blacktop extractors.
Next mod is an SC14 supercharger and a front mount intercooler.

[fixeruperer]

you can have as big throttle body as you want but that inlet manifold isnt going to flow it as the stock gze manifold is poo.
The inlet port on top of the inlet manifold is tiny and so is the inlet pipe bolted to it. You can port the shit out of the manifold and cut/shut that pipe bolted to it. (you may have to space the throttle body inlet pipe bolted to the firewall side of the manifold away as the cut/shut pipe may hit)

my gze used to make good power into the 8k range and pulled hard for what it was but that was port n polished every where.

i used to have photos but there long gone now.


i spent ages in my driveway tuning my gze with big cooler to idle with a microtech tho i got it in the end.

[Drifty Midship]

A mate told me the VSV drops the pressure at idle to help economy. Any salt in that?

[Duk]

A mate told me the VSV drops the pressure at idle to help economy. Any salt in that?

The VSV temporarily opens the FPR signal to atmospheric pressure (higher than cruise vacuum) for a squirt of exstra fuel pressure and a slightly richer mixture.
Something to do with emissions and archaic engine management systems.

[Drifty Midship]

Thanks for the great answers...
I'll leave the TB as is while using the stock manifold then.
Just trying to get the ecu in for now but Cams, gears and portpolish are planned down the track with a spare bigport head
i'll leave the stock FPR then and do the nightmare job of removing a fuel tank in an AW11 and upgrade the intank pump to a high vol one. that will keep me and new engine happy.
Terra, My car has always had stalling problems coming up to lights and think this is ISCV related (or ECU) but i've had it apart a few times and tried to fix many ways so just feel some kind of remote setup is the way to go now. EF Falcon looks like a good unit and easy for the adaptronic to control.
Ive got a ST205 w2a cooler mounted over the gearbox but the intake piping is a little longer than stock by about 40cm.

[Drifty Midship]

The VSV temporarily opens the FPR signal to atmospheric pressure (higher than cruise vacuum) for a squirt of exstra fuel pressure and a slightly richer mixture.
Something to do with emissions and archaic engine management systems.

I think can set that in the adaptronic.
Basically a difference in TPS and load creates an extra fuel trim.
Knows I am jamming the throttle.

[Drifty Midship]

'nother dumb question...
Is the difference in the fuel pressure between the ze and the ge because of the fpr, or the rail or injector flow volume?
If its the reg could you put the ge fpr onto a ze fuel rail for more pressure (more fuel ) ?

[TERRA Operative]

Dunno, but when I set my Sard FPR more than about one PSI above stock on the stock ECU, the car bogs down at takeoff and doesn't rev to redline properly. I guess due to over fuelling.

I removed all the VSV's and have my FPR referencing manifold pressure directly (I also use a Sard FPR, but it makes no difference what you use to the setup).
I also have the ABV directly referencing manifold pressure (ABV mod) to allow more boost to be held.
With stock SC and crank pulleys, the ABV mod, a 3SGTE throttle body, Apex'i pod filter on a cold air induction system and retarded exhaust cams (3 degrees with HKS cam pulleys) I am pulling 10.5 PSI boost on my AE101 4AGZE.
I dynoed 140Hp at the wheels with just the ABV mod and a 4AGE throttle body. I don't know what it's pulling now, I'll be getting it re dynoed once the SC14 supercharger is in.

[Hen]

Is the difference in the fuel pressure between the ze and the ge because of the fpr, or the rail or injector flow volume?
If its the reg could you put the ge fpr onto a ze fuel rail for more pressure?

1 - FPR. Rail and injector flow have no effect on fuel pressure, unless of course your fuel pump can't keep up with the injector usage. Then the rail pressure starts to drop below the FPRs set pressure.

2 - Yes you can whack a GE regulator on (once you go adaptronic). It'll just mean that you can support a little more power for a given injector duty cycle. Not really required, especially if you are fitting 440s.

Hen