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Discussion Starter #1 (Edited)
allright guys im swapping a JDM D15B ECU controlled twincarb engine to a DOHC ZC. As there is pretty much no info about B15B twincarb electronics I figured I just post everything about it here so other people can check this in the future and some people can help me out here. The Problem is that the ECU of the D15B is completely different (for example it only has two plugs.)

So I can do 3 things.

Option 1 - Get a wire loom from a full option 1990 JDM crx SI so i wont loose any options and I dont have to swap wiring. That would be easiest but I highly doubt i will fint that

Option 2 - Get an edm dohc zc wire loom and convert that to rhd. The advantage is that the engine will work directly but I will loose all of my options, such as auto aircon, intermediate wiper, power windows, power folding mirrors, heated seats etc.

Option 3 - Wire up the ECU by myself. This is the option Ill be taking. It's because there is a lot of information about the ZC wiring (its pretty much the same as a b16a1 minus the vtec wiring.

My idea is to use a combination of the old wire loom and then add the new sensors and route everything to the ECU.

First up:

This is the only pinout I can find of the D15B ecu

Its incomplete and it does not show wire colors but it's something

This is a B16a1 ecu pinout, which is the same for the dohc zc im using except for the vtec plugs and the secondary o2 sensor

My first thought was to plug in the dohc zc loom as it has 2 same plugs and 2 plugs extra (so I only have to wire up the additional 2 plugs) Although the pinout of the big rectangular plug at the fuse box side is the same, the other one had a completely different pinout. Thats why it seems easier to just keep the old wire loom.

The OBD0 sensors that the D15B wire loom has:
3 wires green plug blue wire needs to go to the ecu pin B14
1 wire to fuse box (can remain unchanged)
-oil pressure switch goes to cluster so that does not need to be changed
-Coolant fan switch can remain unchanged
-Knock sensor (im not going to use it as the new engine one does not have it)
-Starter solenoid can remain unchanged
-back up light switch can remain unchanged
-o2 sensor 1 needs to go to the ecu pin C16
-Ignition coil can remain unchanged
-engine coolant temp sending unit can remain unchanged
-Engine coolant temp sensor

And some other plugs but they are to control the carbs and not related to the swap so i wont bother looking up what they are

The ones I need to add
-Dohc sensor
-Second plug on distributor (TDC/CKP/CYP)
-injector 1 to 4 with resistorbox
-intake air temperature sensor
-throttle position sensor
-idle air control valve
-map sensor

2,003 Posts
Use carbs and the d15b dizzy with the ZC? Unless you are super attached to FI, I would seriously consider this route.

How was fuel pumping handeled on the db15? If it was a cam driven fuel pump, you will have to do something about that as well.
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