im doing a conversion on my old mk 3 xr3i all the running gear is in ecus mounted etc ive got my loom coming in the next couple of days, but its a s2 loom and i wanted to keep the mk3 auxilary lights etc and dont wasnt to swap the whole loom, i must be able to keep all my existing loom and splice into my old to power the engine i already got the fueling sorted cause its a xr3i anyway and got the pump etc, which wires do i need to connect on the new loom, any help realy appreciated thanks in advance cheers matt

 

there is a lot.

You have a load of sensors, an extra ecu, metering head connections, amal valve connections etc.

Would be much better to use the s2 ecu, and then add bits into it as you need.

 

could try efi, a lot less wiring to do.

 

The easiest way to do it is as i did it.

I have a MK3 cabby, which was an XR3i, i patched in S2 wiring into the original loom and removed all the redundant wiring:



Thats the finished article, i left the coil wires outside of the loom like a proper RS loom. I even wired in the KE Protection module into the fuse box (yes it was very fiddly though ) A bit of time and care and no-one would ever know

 

i would - u've just told me

 

Fairplay. I wouldn't expect you even to know after i told you. Obviously you are not as stupid as you look

 

i know, i am quite stupid...

 

safechav, thats exactly wat i want to do, leave my loom as it is, head lamps, indicators, fan ,auxilary warning stuff etc ect. when i get the new loom most of it can go i all ready got the hearts diamonds ecu and the jetronic mounted all ready, its just a case of stripping the new one down and finding which ones go where theres only max ten wire to splice in to power its just knowing where, i keep looking it the haynes its giving me a headache btw its a s2 loom let me know what u think ,apart from scrap it lol cheers matt

 

Scrap it?

Tits

Its not actually that hard, as you say there is only a handful of wires to connect. I'd say the hardest part is actually removing the old stuff, and laying the new wires in and amking it look good.

Personally though, while you are still in the early stages, i would consider EFI, it will be a lot less hassle and more reliable AND worthwhile in the long run. The wiring is pretty much the same for EFI, its not hard

 

pmsl i know what your saying ,its on a budget i spent more than i thought i would and i got all mfi stuff . im ok with stripping it down and splicing in its just wires and coulors and what goes where, 12v+, switched earth? etc also ive already got the 3i pump in car allready wireing can i leave that in or do i have to conect into that relay? any info much apreciated m8 cheers

 

You can get FRSt stuff for about the same amount, and in terms on reliability its a lot better, although there arent many places that map it. Thats what i would advise if you are on a budget.

Apparently the 3i pump isn't the same, there seems to be a lot of controversy over this though, i myself run a 3i pump at present......

For the wiring, have a look yourself to start with, as i think looking for yourself will help you understand it and then i can check how you've done

All the letters on the S2 diagram will have labels such as B, C, etc, cross reference them back to the 86-90 ignition diagrams, and then you can look the colours up for yours on the 80-86 ignition diagram

 

ill get it going on mfi first as i all ready got the bits but as someone informed me i can go efi as i got the hole for the pick up, yea ill get it and as u say cross reference it i thought it was the same as going from a 12v 2.9 to a 24v just a handfull of wires n loom to connect ill have a go, and btw your fuel pump the stuff i bought i got a pump with it , looks the same but im assured its no? from the haynes
k jetronic minimum in 30 secs0.7 liters
s1 turbo minimum ke jet 1.1 in 60 secs!
s2 ke jet 2.5 in 60 secs
work it out for ur self , whys the s2 got a bigger fuel output? im gonna swap it anyhow but why

 

I know what you are saying about the pumps, ive had people re-assure me they are the same however, and others disagree. I'd love to get my hands on a new one of each to answer the question myself by the bosch part numbers