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MG MGB GT V8 Factory Originals Technical - EFI Question

I'm interested to know where & how the various componants of a Rover EFI are installed in an MGB. The ECU for eg. under the dash, in the passenger footwell, under a seat? I think with the wiring loom I have, I could mount it in the boot/trunk ! Where & how did you mount the flow meter, power resistor, relays etc. Where about did you cut the hole for the loom to pass into the cabin area ? I want to try & get it right first time by taking a proven method. Thanks in advance for any replies. Barrie E.
Barrie Egerton

I'm guessing you've a Hot wire since you mention a tune resistor.
I'm at work so can't do links etc.. so try the archive material.
EFI Stepper motor question
Phenum welding & Lamda sensor voltage
Were two questions I posted and got outstanding help on.
Any search on Hot Wire or EFI or Fuel injection should get you useful stuff with links to efi trouble shooting sites. May be some else could post a link here?

Specifically I;
found that you don't need to cut any holes, the rubber surround/plug on the rover hot wire efi loom is the same as those two rubber plugs in the MGB engine compartment and substiutes nicly allowing me to feed the relays and computer plug through the hole above the passengerside foot well.
I located the computer beneathe the glove box, I hooked one side (of computer)over the cross brace and secured the other by one long bolt. The two relays (and tune resistor (470 ohm, non cat') just sit ontop of the computer unsecurred. You might want to make a better job of it?. The computer has three wires which need to be wired into your MG. The Computer power, the fuel pump power and the ignition wire. You will need to lengthen all of these three to reach back to the fusebox.
There is also a wire to the distributor and coil from the loom.(I'll check and get back to you on colour, I don't recall at the moment) I ended up buying a rover haynes manual for the wiring diagram.
I sustituted the old MGB 4 fuse fusebox for a new 8 fuse after market item. I needed a seperate fuse for the EFI power, the EFI fuel pump/relay and a seperate fuse for the EFI off the ignition (playing safe).
I had to unwrapp the loom, lay it where I wanted it to run, then gather/double up any excess. I don't believe you can shorten any of the sensor wires as these will have a resistance that has been allowed for, but you can do what you like with the power supply lines.
Visually I ended up with a cable with ran from the fuse box across the back of the alternator, then tucked in between the fuel rail and plenum back along the motor. Quite neat.
I got rid of the fan timer delay stuff (big green relay & yellow relays))as with the large fan I'm using I didn't like the idea of it running for 10 minutes after I shut off the motor. I use an overflow tank.
The 95 range rover air intake has a big rubber elbow that sets up nicly for the MGB and locates the airflow meter forward & just near the spot where the old radiator surround used to attach (guess what's attached there now?)

PS As of yesterday I'm now officialy legaly on the road!

Wireing for my '94 ish Hot wire EFI.
Thick Purple with white stripe is fuel pump relay
& Thick white with purple stripe runs back to the fuel pump.
Thick Brown with orange stripe is power for computer
Thin white/green (green/white?) is the ignition.

It is a little more confusing between the coil and distributor, or at least my memory fails me and the detail is all wrapped up.
On the coil positive is a red wire and a white green wire.
On the coil negative is a blue wire.

From what I can remember two distributor wires run to the coil, and one runs back to the computer via a resistor, if you really get stuck on this I'll unwrap that part of the loom and have a look as the Haynes book differs and isn't much help.

This thread was discussed on 16/08/2003

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