V8 SU -> EFi conversion

[HoSS]

So, I'm planning to do a 2 phase upgrade on my V8 3.5

Phase one will be to fit EDIS & MegaJolt.

Phase two will be EFI conversion using a MegaSquirt to control the system.

I have managed to find a Inlet manifold with injectors & plenum.

I will need to find a MAF sensor ( i guess any generic one will do for MS)

I hear that a high pressure fuel pump ies required, how are these identified?

Any other parts that i need?

Cheers

[Hybrid_From_Hell]

For efi you wnat efi heads as well, injectors mean that there is a difference, can be done but fitting efi heads easier.

HP Pump get from from a RR

With the EFI theres a load of bits you'll need on top of the inlet / plenum

ECU, HArness, AFM, PRV, HP Pump, Extra Air vave (assuming flapper), Resistor pack fuel rail etc etc etc, have a good study of the system, often easier to buy a big end gone full motor

Hotwire is differet again, and parts are not generally interchangable

Nige

[HoSS]

For efi you wnat efi heads as well, injectors mean that there is a difference, can be done but fitting efi heads easier.

HP Pump get from from a RR

With the EFI theres a load of bits you'll need on top of the inlet / plenum

ECU, HArness, AFM, PRV, HP Pump, Extra Air vave (assuming flapper), Resistor pack fuel rail etc etc etc, have a good study of the system, often easier to buy a big end gone full motor

Hotwire is differet again, and parts are not generally interchangable

Nige

Ah, how different are the heads? I hadn't anticipated changing them.

Don't need ECU, Harness - cos will be using Megasquirt.

Wot's a PRV?

Extra air valve, required why?

Resistor pack - does what?

Fuel rail i have on the manifolds.

bought this - http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...N%3AIT&rd=1

for 7 quid, cant go too wrong...

[Hybrid_From_Hell]

There are many here far more up on this conversion than me, but what I can tell you is

(also assuming this is a EFI Fallper not Hotwire)

Megajolt :

You'll need (on top of the MegaJolt)

Flapper System :

Manifold assembly, this incs Plenum body and throttle body

Injection ECU wiring harness

Air Flow Meter

HP Fuel Pump

2 Injector relays and steering module (a diode pack)

Power Resistaor Pack

ECU

2x heads

On the manifold is a fuelk rail, a PRV (Fuel press relief valve), extar air value loads of rubber pipes and sensors ie cold start, coolant temp 8 injectors, thermotine switch, throttle potentiomete

breather pipes

Hotwire is less.

Manifold assemble incs plenum and throttle body

AFM

and connections

ECU Wiring Harness

HP Pump

Road speed transducer

ECU

2x heads

On the manifold : 8x injectors, coolant temp thermistor, steeper vave, fuel rail, PRV, Potentiometer, Breather pipes Thottle mechanisim etc

If you MegaSquirt it then you need less, but I am NOT 100% sure but think you'll still need

Flapper System :

Manifold assembly, this incs Plenum body and throttle body

Injection ECU wiring harness or make your own up

HP Fuel Pump

2 Injector relays and steering module (a diode pack)

2x heads

On the manifold is a fuel rail, a PRV (Fuel press relief valve), extar air value loads of rubber pipes and sensors ie cold start, coolant temp 8 injectors, thermotine switch, throttle potentiometer

breather pipes

Hotwire is less.

Manifold assemble incs plenum and throttle body

ECU Wiring Harness or make one

HP Pump

Road speed transducer

2x heads

On the manifold : 8x injectors, coolant temp thermistor, steeper vave, fuel rail, PRV, Potentiometer, Breather pipes etc

Nige

[FridgeFreezer]

Close.

Hoss - why use MegaJolt then go to MegaSquirt, the MS ECU will do the "jolt" bit as well, you sound like you may end up using two boxes when one will do! Looky here for full info.

You don't need a MAF sensor for megasquirt, it uses a MAP sensor mounted on the board.

I'd be inclined to get the engine running MegaSquirt first as this is easy - chop Lucas ECU plug off, join a few wires and plug in MS ECU, not much else apart from adding the lambda sensor & air temp sensor. Fuel maps are available online, search the tech archive for MegaSquirt.

Extra air valve on flappers is a funny shaped thing in front of the plenum chamber with a hose going to & from it, all you need to do is feed it +12 ignition switched (I think it's the white/light green wire) which I wire into the fuel pump relay on MS installs. On Hotwire systems they have a stepper motor thing on the rear of the plenum, that's a bit more involved but the MS can control it if needed. I blocked mine off and it ran fine, just needed to idle for a few seconds on cold mornings before pulling away.

There's not much difference in the heads, you'd probably get away without them but the little notch where the injector fires is obviously there for a reason.

Thermotime switch and 9th injector (on side of plenum) are not needed with MS, nor is the Lucas AFM.

Injectors, fuel rail & pressure regulator should all be on your manifold. I see it's missing trumpets and plenum, that could mean buying another complete setup in the end as they don't crop up seprarately that often, if they do it's probably still cheaper to buy a complete setup, I pay ~£10 each at Sodbury for them.

[HoSS]

I'd already ordered the MJ before i decided to investigate the EFI. Anyway its a good 1st phase to get the EDIS parts working before going to phase 2. I can always sell on the MJ afterwards.

Extra air valve - Is that the thing in the picture here? - http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...N%3AIT&rd=1

I bought the plenum & trumpets in his separate auction below, so i seems to have the throttle body/ position potentiometer also- http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...N:IT&ih=017

Theres no downside to using MAP over MAF control? Actually i heard MAF sensor is more prone do damage if bounced about too much.

I wonder - could someone take me a clear phot of thier standard/or hybrid EFI setup, so i can see where pipes etc go?

Cheers, HoSS

[Hybrid_From_Hell]

This is the Eales after rebuilt

AFM is JAG 4.2 looks the same but a tad bigger, AirBox is moded but other than that its sort of the same as a 3.5 EFI FLapper system :

Nige

[Bull Bar Cowboy]

Ah, how different are the heads? I hadn't anticipated changing them.

Don't need ECU, Harness - cos will be using Megasquirt.

Wot's a PRV?

Extra air valve, required why?

Resistor pack - does what?

Fuel rail i have on the manifolds.

Right lets take your questions one by one,

Ah, how different are the heads? I hadn't anticipated changing them ?

Unless your engine is pre SD1 then the heads are identical apart from small cut-outs in the inlet ports adjacent to each injector ............. you can easily cut these with a dremel as I did on mine, but it is rumoured that the cut-out makes very little difference ......... indeed, I have seen EFI's without them that run perfectly well. I can understand this as it is not sequential port injection ......... the injector banks fire as two banks of four, so its a 'just dump a load of fuel in the manifold type of injection'. Use the EFI inlet manifold gasket as a template to notch the heads.

Don't need ECU, Harness - cos will be using Megasquirt ?

OK ............ yes its easy to construct a loom ........ the injector plugs and sensor plugs are available from VWP. I noticed that in the picture of what you have purchased, a major part of the harness is there.

Wot's a PRV?

Not the true description ........... its a fuel regulator that lives on the fuel rail. It is vacuum controlled and returns unused fuel to the tank. Its function is to control the fuel pressure in a linear manner when above tick over, and to reduce the pressure by 0.5 bar during tickover. Most of us that run EFI use an after market 'Rising Rate Fuel Regulator' this has benefits over the standard item as it is adjustable for fuel pressure and also delivers fuel at almost twice the rate of the OEM item when accelerating from a standstill thus eliminating flat spots and weak running. The OEM regulator is prone to failure and after a few year use they become very lazy …….. also it is a none adjustable other than to gently squeeze the case to get the desired pressure …….. very hit ‘n’ miss ……. In fact more miss then hit.

Extra air valve, required why?

The extra air valve is used to admit more air into the inlet when the engine is cold ........... thus make the engine tick over at a higher speed (1200 rpm). It is a bimetal valve that is usually in line connected via the fuel pump. Current flowing through the internal coil heats the bimetal valve to slowly close off the air. Once the engine is at normal temperature a warm start is unaffected as the position of the valve (mounted on the hottest part of the inlet manifold) ensures that the valve stays closed due to latent heat. The hot wire systems use an IAC (Idle Air Control) stepper motor which is mounted on the rear of the plenum. IMHO this is a superior solution. I believe that MS-II can control an IAC stepper.

It should be noted that the cold start is also assisted by the ECU detecting the engine temp from the temp sender, thus supplying more fuel. The Flapper system also has the thermotime switch that activates the 9th injector, however, it has to be very f'ing cold for this to happen.

Resistor pack - does what?

The resistor pack is only used on the Flapper injection as this uses low resistance (often incorrectly called low impedance) 3 volt injectors. The resistors perform a current limiting function and therefore reduce the final voltage / current to acceptable levels for the injectors. The Hot wire does not need this as it uses high resistance (12v) injectors. Many believe that the flapper low resistance injectors are superior ....... maybe that’s true. The resistor pack is not particularly robust and has an intense dislike for water. It also uses Molex connectors which are renowned for being carp. I am in the process of redesigning my resistor pack so that it lives in the cab with the ECU.

Fuel rail I have on the manifolds

Yes, if you have the injectors, then they will be connected to the fuel rail with the fuel regulator on the end.

EFI Fuel Pump ?

The pukcas EFI system is not very fuel demanding and most second hand (or if you are posh .... pre owned) pumps will do the job ........... here are a few that I know work ......... EFI Metro, EFI Montego, Poxhall Cavalier, Sierra 4x4, EFI Granada................... remember that you also need an EFI fuel filter........ use the RR EFI inline filter and change at 20K intervals. The pump must be mounted very near to the tank as their design means that they are very good at pushing but not so good at sucking. If it helps, I use the Sierra 4x4 pump and that has been excellent.

What Else ?

As you are going MS then you don’t need the Flapper air flow meter, or the vacuum operated overrun cut off switch ......... but you will need to fit an air temperature sensor into the plenum. The vacuum cut-off is a good idea if you want maximum engine breaking on downhill descents and to also save a tiny bit of fuel. It operates under very high manifold vacuum (overrun) and disconnects the fuel pump

Ian

[HoSS]

Cheers guys, thats some top-notch info.

I've no doubt I'll have some more questions when i've assembled all the bits & start the install.

Cheers!

[HoSS]

Actually, 2 more questions:

Where does one find one of those 'Rising Rate Fuel Regulator'

I have the in-tank pump currently, what would i do - add the HP pump externally & suck through the old one?

I can see any other way to modify the pick up easily.

[Bull Bar Cowboy]

Rising rate Regulators can be bought from RPI , V8 Developments, JE , & Rip off Bros ……. You’re looking at £70 - £90 for something decent.

You could use the internal pump as a lift pump, or you could pull it out and fit a bypass pipe and then refit ……….. some have just left it as is and disconnected ……… this seems to work OK but is not ideal.

Ian

[HoSS]

Does anyone know if the RR classic (efi) HP in-tank pump (PRC8318) will fit the 110 Defender tank?

Also it looks like the RR classic has no fuel return line, is that true for all Efi's?

[Bull Bar Cowboy]

I am fairly sure that the internal RRC EFI pump will not fit a Def tank……..

All EFI’s must have a return……… its because the injectors must receive more fuel than they need (i.e. its pressure fed …. 38 psi for a flapper system)…….. and unwanted fuel is returned to the tank…….. the continual fuel circulation also aids the injector cooling.

Ian

[HoSS]

I am fairly sure that the internal RRC EFI pump will not fit a Def tank……..

All EFI’s must have a return……… its because the injectors must receive more fuel than they need (i.e. its pressure fed …. 38 psi for a flapper system)…….. and unwanted fuel is returned to the tank…….. the continual fuel circulation also aids the injector cooling.

Ian

Hmm if you look PRC8318 up on EPC, firstly the tank looks just like the 110 tank, but also there does not seem to be a return pipe onto the pump. And that is for the Efi RR classic apparently.

[Hybrid_From_Hell]

I had a low pressure In tank pump in the 90 which had a V8 3.5 carb engine.

I took a Range Rover classic pump apart, and put the 2 of them togther making a HP pump which fitted to the parts from the LP pump which I then popped back in the tank, and popped in a HP RR Classic Fuel filter too (LP filter is not up to the jobbuie)

The 90s tank has a seperate return....

HTH ?

Nige

[HoSS]

Actually i'm talking b......ks, the LP pump i have has a separate return anyway. I do reckon the RR classic HP pump will fit looking at the EPC. The later plastic tank pump is different, yes.

[Hybrid_From_Hell]

Yep

Mine LP and HP had a similar top with 5 or 6 screws, this had then a tube thiny which went down to 2 bolts that had the HP LP pumps on, and then the wires which clip onto the top etc

Its basically a swap around, the main difference was the overall length of the pump LP Vs HP, so I used the bits from the LP to get the right length overall, and the bits from the HP to give me er HP

Nige

[FridgeFreezer]

Rising Rate Fuel Regulator' this has benefits over the standard item

It does if you're using non-tunable EFi, with MS you don't need to "cheat" by raising the fuel pressure, you just raise the fuel map to the correct level.

detecting the engine temp from the temp sender, thus supplying more fuel.

You'll find this in the MS settings under "warmup enrichment", it can take a while to get right as you have to tune it before the engine gets warmed up.

The Flapper system also has the thermotime switch that activates the 9th injector, however, it has to be very f'ing cold for this to happen

You can ditch the 9th injector with MS, indeed it was ditched after the flapper system. The hole in the plenum makes an ideal mounting for the air temperature sensor.

Many believe that the flapper low resistance injectors are superior ....... maybe that’s true.

There is rumour that Low-Z injectors + resistors work better (more accurate opening time?) than high-Z ones, or low-Z ones with PWM current limiting from the ECU. I know SimonR tried to run the low-z ones with PWM and it didn't work. If you run PWM you may want to add a flyback board to the MS (I can't recall if the V3 ones have this built in) to catch the large voltage spikes this can cause.

It operates under very high manifold vacuum (overrun) and disconnects the fuel pump

Close - it actually operates a relay next to the coil which disconnects the coil (TACH) signal to the ECU so that the ECU stops injecting fuel. After a couple of seconds of no TACH signal the ECU assumes the engine is stopped and shuts off the fuel pump - MS also does not run the fuel pump unless it sees ignition events, this is a safety feature and IMHO quite a handy one in off-roading.

The whole valve/relay setup though is IMHO a weak link as a dodgy connection or duff relay can cause your engine to stop. I tend to bypass it.

The vacuum cut-off is a good idea if you want maximum engine breaking on downhill descents

I'd beg to differ here - why not just drop the fuel map to zero rather than have the "point of failure" that this introduces.

What would i do - add the HP pump externally & suck through the old one?

Yes, this is a good idea as the lift pump supplies a bit of head to the EFi pump, which makes it's life much easier. EFi pumps (unless they're in-tank) really don't like sucking fuel. I know several people (coughREDIBEXcough ) who have killed multiple EFi pumps this way, even mounted as Ian suggests close to the tank.

I used a Facet LP fuel pump to feed a Cavalier EFi pump on the 109 and it worked well. While you're on the fuel system, a small swirl pot is a good dea, there is a Land Rover one that is cheap to buy and works very well:

I actually noticed the EFi pump note drop and the fuelling got much better / more reliable with this installed.

On the advice of a friend I added a small inline fuel filter to the "return" of the swirl pot to create a bit of back pressure (aids the purging of vapour aparrently), as well as in the return from the PRV - I find being able to see the fuel return is very handy in diagnosing problems as you can see when the pump is running, if fuel/vapour is circulating, if the PRV has failed (no flow despite fuel going in) etc. This tends to be one of the first things I do to diagnose "dead" flapper vehicles.

[HoSS]

Thanks FF.

After a bit of a clean-up, i suggest this thread is dropped into the Technical Archive perhaps?

[western]

Thanks FF.

After a bit of a clean-up, i suggest this thread is dropped into the Technical Archive perhaps?

Just tell me when & I'll transfer it to Tech Archive a live link will remain here to the thread.

[Bull Bar Cowboy]

It operates under very high manifold vacuum (overrun) and disconnects the fuel pump

Close - it actually operates a relay next to the coil which disconnects the coil (TACH) signal to the ECU so that the ECU stops injecting fuel. After a couple of seconds of no TACH signal the ECU assumes the engine is stopped and shuts off the fuel pump - MS also does not run the fuel pump unless it sees ignition events, this is a safety feature and IMHO quite a handy one in off-roading.

The whole valve/relay setup though is IMHO a weak link as a dodgy connection or duff relay can cause your engine to stop. I tend to bypass it.

The vacuum cut-off is a good idea if you want maximum engine breaking on downhill descents

I'd beg to differ here - why not just drop the fuel map to zero rather than have the "point of failure" that this introduces.

Sorry John ………………. I modded mine to directly shut off the pump via the pump relay . For those who need to identify the over run shut off relay ………….. its normally mounted beside the flapper.

But yes FF is right ………….. the normal course of events is the vacuum switch operates and kills the ‘ORS’ relay supply, which removes the Tach signal from pin 1 of the 14CU ECU. The ECU then signals ’shut off’ to the pump, by removing the supply to the pump relay. A common source of EFI burnt wiring looms is the feed to the Vacuum switch chaffing to earth on the rear engine lift bracket.

Fuel Pumps.

The most successful pump in terms of ability to suck and well good forward pressure, is the Ford from the sierra and granny EFI’s ………….. IIRC they will pump at 60psi……….. but we only need 38psi. They have Bosch part number ……… I can’t remember what it is though. Current wise this one is a bit of a beast and draws a continuous 7 – 10 amps ……… fuse at 15amps. Also the input is an odd size ……… something like 1/2 or maybe 5/8………. bigger than most common fuel hose sizes.

I will admit to having some problems (only because I am fastidious bar steward when it comes to engines) with EFI pumps from other ‘L’ injection systems. The problems were either the pump felt too hot or the fuel supply was marginal under high RPM/Load conditions ……… however, as mentioned above, the Ford unit cured all those problems …………. so I guess the swirl pot would work well with those pumps.

It should also be noted that the fuel also cools the injectors ………. that is why when running a standard gas system (not sequential inj) the original fuel system must be left intact to circulate fuel into the rail and returning to the tank via the regulator. If this is not done, then often the injectors get cooked.

Most fuel pump failures that I have been involved with are due to them being ‘on the edge’ and not supplying enough ‘through put’ via the regulator to keep them cool ……… it’s the fuel that provides all the pump cooling.

Overrun Breaking.

Yes, as long as dropping the fuel map to zero completely shuts the injectors down then the effect is the same.

Injectors.

I am in the process of going over to MS V3 …………. I will retain the Low R injectors and construct a resistor pack using modern reliable resistors and connectors to be fitting in the cab along side the MS ECU

Ninth injector

Some moons ago, I tried to work out at what air temp it was active ……….. IIRC the air temp needed to be well below 0C !

However, the feed to the 9th injector is a handy place for testing the fuel rail pressure

In short ……………… yes the flapper system can be made to work very well indeed and is streets ahead of any carb system (especially in many off road situations)………… however, the MS system is streets ahead of both with its versatility, tunability and above all ‘implementation economy’………. Amen

Ian

[FridgeFreezer]

I will retain the Low R injectors and construct a resistor pack using modern reliable resistors and connectors

You could construct it from modern and reliable string and paper clips compared to Lucas implementation

[HoSS]

Can somone help me out with what a few of these parts are & where they are normally connected?

A, B & D appear to be water temp senders (but why 3?, gauge/ECU/+?)

C seems to be a thermoswitch - used for fan?

What are E & F?

[Bull Bar Cowboy]

A = temperature gauge sender

B= Rad fan switch ……… most likely came from an aircon vehicle …….. this type of thermostat housing is expensive (£65) ………the switch is the standard 22mm thread.

C= Thermotime switch for the ECU ……….. decides whether to fire the 9th injector and for how long.

D= Water temperature sensor for the ECU

E= need a better picture to see what it is ………. Normally there is nothing in that position on a flapper

F= Overrun cutoff switch ……… it’s a vacuum switch that disconnects the supply to the overrun cutoff relay, thus disconnecting the rpm signal from the coil to pin 1 of the ECU

Give me a better picture of E ....... it looks like the fuel regulator ......... but it should not be in that position.

HTH

Ian

[HoSS]

thanks BBC.

another pic, best i have at the mo.

E is not the fuel reg, that is where it should be behind.

It has one black wire coming out & seems to be air rather than fuel.