Twin 45 Weber Conversion

[Guest nelly023]

I am in the process of fitting weber 45's and although the fitting guide on the forum website has been useful it looks as though the wiring diagram included shows how you sort out the ignition if you have a traditional coil. I have a later 1991 car with the coil pack mounted on the inlet manifold. Can anyone let me know what i need to do to this to ensure the ignition side still works.

Thanks

[porter_bmx 0]

all i did was un plug the injectors, air flow meter etc which you no longer need. You can either remove them from the loom or leave them un pluged. The ignition will work fine just make sure you leave the plug which connects at the distributer other wise it won't run.

[Guest nelly023]

all i did was un plug the injectors, air flow meter etc which you no longer need. You can either remove them from the loom or leave them un pluged. The ignition will work fine just make sure you leave the plug which connects at the distributer other wise it won't run.

 

Thanks very much for the reply. I was hoping that would be the case. Regards.

[woodsy 0]

Thats what i did really, cut out all the unecessary wires (airflow,injectors,throttle switch etc) and had the rest of loom running across bulkhead.Mounted coil at corner of pass side bulkhead out the way under the expansion tank.

[Guest nelly023]

Thats what i did really, cut out all the unecessary wires (airflow,injectors,throttle switch etc) and had the rest of loom running across bulkhead.Mounted coil at corner of pass side bulkhead out the way under the expansion tank.

thanks for your reply. i've been on it all day today but have encountered a problem. the electric fuel pump i've fitted is running but i don't seem to be getting any fuel through. I'm pretty sure i've connected the pump to the supply rather than return pipe. Are you able to confirm that on yours this was the right hand pipe as you look at it which was originaly connected to the injector rail. what did you do with the return feed? Any other thoughts are appreciated

[woodsy 0]

The pipe that was originally going into the bottom of the fuel filter is the one you should have going into the bottom of electric pump.The return pipe was just cut at bulkhead and blank put on end as you dont require it.Iam using a Facet pump is that what you have.

[Guest nelly023]

The pipe that was originally going into the bottom of the fuel filter is the one you should have going into the bottom of electric pump.The return pipe was just cut at bulkhead and blank put on end as you dont require it.Iam using a Facet pump is that what you have.

Yeh i'm running a facet too and had connected it to the pipe which was connected to the bottom of the fuel filter. I'm gonna connect the pump to the pipe at the tank end to rule out the pump and work forward from there.

[Dazza 4]

As the guys say nelly , real easy to do this conversion.

 

Fuelling can be done 2 ways;

 

A. leave the origional fuel pump and allow exess pressure to return via an 8mm T piece to the tank and the other feed goes through a filter king pressure regulator.(gives approx 3 psi automatically)

 

B. Do it propperly and take out the pump and fit a pick up, utilise the fuel supply pipe and fit a new 6mm pipe from the feed pipe on the bulk head to the Facet then to a pressure filter king and set to approx 3 psi. Just blank the return feed

 

The wiring is easy to with either so presume B is your way then unplug the ecu/ tach relay and all loom to the injectors etc, iirc the whole brown plug so the injectors-throttle switch and AFM/cold start are taken out.

 

The negative side of the Coil feeds the rev counter so thats fine and please dont forget you no have NO REV LIMITER....so it wll go bang if your caught with a wide open throttle pedal....

 

You can fit an Omex clubman £90 and this allows the adjustment of the limiter to what ever you like and has a shift light to, real easy to fit to 3 wires that are positive feed--- negative feed and a blue wire to the neg on the coil that reads the pulse and transfers this to earth effectively Earthing/killing the spark at the permitted limit you set.

 

The throttle linkage is best adapted to run twin cables and linkage, you can modify the pedal arm to accept the cables quite easily.

 

So there you go ....enjoy the noise !

Edited July 26, 2010 by Dazza

[woodsy 0]

If your still not getting fuel through maybe worth checking what you have done to the pick up in tank.I removed pump and think left cage there and put length of fuel return pipe in place of pump but measured how deep it should be compared to old pump.

[FirSt95 0]

The king regulator, soported the pressure of the standard pump?

[MrG 3]

the filter king regulator will support and reduce the pressure from the std inj pump, as thats what I have on mine.

[Dazza 4]

Are you sure ? I used a 8mm T piece fuel return setup with the inj pump and filter King. I think you need to review that one . Then I used the propper set up .

[samc 1]

i used a malapassi reglator and used the return out the bottom of it to go back to the tank, worked a treat

[MrG 3]

well I've used it in this way for 2 years now and all is good in the MrG camp. But if I was to fit a T piece to return fuel to the tank, where would it be installed? After the regulator I take it. If so will this not reduce the pressure to the carbs? Mines spot of 5 psi from the reg.

[MrG 3]

also need to point out that I get no fuel surge issues either unlike a few I know who have carbs, so would this be an issue at all?

[Dazza 4]

On mIne before the new set-up it was inj fuel pump through origional filter then 8mm union and pipe fitting to the T piece and return, then into the filter king and this gave about 3psi to the carbs and was fine all the way to 130 mph.

[Guest nelly023]

As the guys say nelly , real easy to do this conversion.

 

Fuelling can be done 2 ways;

 

A. leave the origional fuel pump and allow exess pressure to return via an 8mm T piece to the tank and the other feed goes through a filter king pressure regulator.(gives approx 3 psi automatically)

 

B. Do it propperly and take out the pump and fit a pick up, utilise the fuel supply pipe and fit a new 6mm pipe from the feed pipe on the bulk head to the Facet then to a pressure filter king and set to approx 3 psi. Just blank the return feed

 

The wiring is easy to with either so presume B is your way then unplug the ecu/ tach relay and all loom to the injectors etc, iirc the whole brown plug so the injectors-throttle switch and AFM/cold start are taken out.

 

The negative side of the Coil feeds the rev counter so thats fine and please dont forget you no have NO REV LIMITER....so it wll go bang if your caught with a wide open throttle pedal....

 

You can fit an Omex clubman £90 and this allows the adjustment of the limiter to what ever you like and has a shift light to, real easy to fit to 3 wires that are positive feed--- negative feed and a blue wire to the neg on the coil that reads the pulse and transfers this to earth effectively Earthing/killing the spark at the permitted limit you set.

 

The throttle linkage is best adapted to run twin cables and linkage, you can modify the pedal arm to accept the cables quite easily.

 

So there you go ....enjoy the noise !

Thanks for all your advice. I've now got it running so just need to get the carbs set up properly. Thanks for the reminder about the rev limiter. I only use it on track so will invest in one of them. I was gonna get a shift light anyway so it'll sort 2 issues out at the same time.

I went down the route of taking out the original pump and put the 8mm pipe into the tank and fitted a facet electric pump and filter king regulator.

Sounds lovely on idle so can wait to give full bananas on a track. I was booked to do Anglesey last weekend but they cancelled at the last minute...Pembrey in Sept is beckoning.

 

Thanks again

[MrG 3]

good stuff, pity you can't do the journey up to Cadwell late in Sept (I appreciate it's a VERY LONG way from you though).