ca18det conversion with s13 clocks

[terry]

Im planning on doing a ca18det conversion into my 89 s12, now im getting the engine gearbox(i know its not needed but mine has 150k on it) s13 prop shaft and the full engine loom with ecu igniter and dropping resistor.

Physically fitting the engine isn't too much of a problem, i understand that i have to cut the tunnel a bit, weld the gearbox mount and make a hybrid s13/s12 propshaft to get things working.

Now what has me confused is the wiring(surprise surprise ), ive read the guide on here and on club s12 and there seems to be a lot of confilcting information about how its done and with a white plug needing splicing??

Id like to hear from people who have actually done this conversion as to how they wired their engine into their car , its also my plan to do an s13 dash conversion down the line with s13 instrument cluster so whats the handiest way to get the speedo working?(it being electrical and the s12 being mechanical)

any information, tips or pointing in the right direction would be great

thanks

[PukkaSilvia]

The white plug is part of the s13 loom. It is situated near where the main plug is that plugs into the ecu. This white plug normally plugs into the car loom of the s13.Obviously as you dont have that plug in the s12 you tee into the wires that you require. If you have a look at the s13 workshop manual it will tell you all you need to know on what is what. You can view this manual at manual pdf

[30psi]

There are 2 wires that you connect to at the white plug being the starter signal wire and the temp gauge wire.

The white plug should be the last of your worries though.

I don't really understand the point of using an S13 instrument cluster.

But if you wanted to you would have to follow the wiring from the speed sensor on the gearbox, which probably goes via the ecu then into the dash via the white plug

[s12Rob]

why would you want to put a det in it. are you cheating? lol

[PukkaSilvia]

starter signal wire? Do you mean an ignition live? as my starter motor exciter wire was part of my car loom and didnt have to be touched at all in the conversion

[30psi]

The starter motor feed is done via that plug.

It could be that yours was taken off near the starter motor itself, but the s13 feeds come via the white plug from the ignition barrel.

If its not connected, it will take a little longer to start thats all

[terry]

cheers , thats cleared most of the wiring confusion up nicely, so do i take it that the 3 relays from the s13 just need splicing into the s12 loom exactly as the guides say?

reason for the s13 clocks is nothing really just to be different as i havnt seen a dash conversion in an s12 before

[PukkaSilvia]

yes. Follow the guide if you need too. Its very straight forward once you have everything in front of you.Do all the obvious bits first and you will find that you only have a few wires left and will wonder what all the fuss is about

[terry]

cool , ill be starting the stripdown in 2 weeks or so so will let you know how im getting on

thanks again

[30psi]

There are lots of wires, it depends how you pull the 3 relays section out of the s13. In neils car I had to tie up about 20 spare wires as temporary measure (never know if they were needed at an early stage so didnt cut them). Some of the wires are the same colour to make things harder.

I'll try to get neil to take pics of where I tapped the wires into the original ecu relay and the battery etc.