NEW ISSUE Quick Electrical Question
Turbo Mini Forums

I am converting my SPI mini to carb, i have found some decent instruction on minimainia. i have got a bit stuck wireing in a relay to replace the ecu. I know the pins i need to use by number but do not know where to start counting? i assume top left will be number one, but which way is up?



I thing number one will be top right in this image and number two will be the one below it?




while i am at it what should the fuel presure be for a hif44 carb on a N/A stock 1275 engine?

also i am useing a regulator without a return feed, is this a bad idea and why?

Thanks guys

Edited by maccamcvey on 9th May, 2011.

Don't know about the electrical plug but the fuel pressure will need to be about 3pis. I think the pump will need to be the type that turns off when the right pressure is reached if your not using a return on the reg.
Not 100% sure on what I say is right but know one eles as replyed so thought I might try to help
Craig

Craig

my mini van http://www.turbominis.co.uk/forums/index.php?p=vt&tid=448248

Cheers craig i was going to start with a low psi but the pump just forced fuel passed the seals on the reg. so i am going to use a Facet pump i was planning on useing on my turbo build. as for the wireing with a bit of guess work the pump works but i am only getting a very week spark, not had much chance to look into this as of yet. the coil is hopefully to blame

your regulator is bad then, a good reg shoudl get an injection pump down to 3psi no sweat.

for the wiring, look inside the connector on the ecu, or on the back of the plug, im sure one or the other has wire numbers, failing that, get a copy of the mg-rover RAVE CD and get the wire colors :)

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

oh aye, and you need to use a regulator with a return feed if your using an injection pump (just noticed that post, sorry)

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Normal protocol with Ampseal connectors is No 1 top left but reading from the back of the plug (the side the wires go in) so would be bottom right in your photo.

RAVE says that No 4 is white/pink (main relay control) and No 20 is black/pink (fuel pump relay) for the SPI so knowing those colours you should be able to check the numbering.

Regulator must have a return as the way they work on an injection pump that runs continuously is by dumping the excess fuel straight back to the tank.

Schrödinger's cat - so which one am I ???

Plumb the fuel flow from the pump into the regulator inlet and the fuel return to the tank onto the regultor outlet. Tee into the fuel flow from the pump and connect that to the carb, set the regulator pressure to 3psi. Job done.

Cheers for you help guys but a little more is needed.....

I am using a Lucas 46d electronic dizzy

When turning the engine by hand (4th gear one wheel in air) I get a good spark from the king and each cylinder.

When I crank the engine on the key I only receive a spark when the ignition is turned off!

I have connected the coil independently, via a completely different battery, and removing the 12v supply provided by the car. It worked perfectly!

There is only a small voltage drop at the +terminal of the coil when using the cars battery.

I have also tried running a cable direct from the cars battery to the coil and I receive the same issue of only sparking on switch off!

The last one is the really confusing bit!

Any help would be much appreciated.

Cheers

Is the engine earth good enough? Is the starter wiring pulling the 12v feed to the coil down somehow? Is it wired through some weird ballast system?

Fairly certain it’s not a ballast system but i could be wrong, not knowing a huge amount about the old spi wiring. Also the earth is good.
I just had it running again, started it as above with a second battery. Started with the 12v feed disconnected. When running i reconnected it, still fine. then disconnected the second battery and it still running fine!
I think it’s got to be something to do with the final switching position on the ignition switch (cranking poss).
No idea what though.
Also it could it be something related to the immobiliser, now there is no ecu telling it what to do it correctly. I still need to switch it off to get it to crank.

have you got a live feed from the starter solenoid that is live on cranking attached to the dizzy ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

I think the orignal live feed to the coil comes from the solenoid via the fuse box and to a load of old sensors.
should it work with a direct feed from the solenoid?

FIXED it was down to a bad 12v supply, i only ever connected it directly to the battery while it was it was being jumpstarted, for some reason now the bat is fully charged it solves the problem, found a good switch live and fanny is you dads brother!