V8 Swap wiring questions
 

Where are you guys putting the factory ECU? Where are you putting the GM ECU? Which O2 sensors are you using and just the 2 main O2? Also what are you doing with the 12" length of the harness that is attached at the engine bay to make it clean?

This is going to be interesting. So how are you fitting both engines in?? I see you are running 2 ECU's one for each motor??

The factory ECU is actually inside the car, not the module that is in the engine bay. That is the injector driver.

Oh thank you for that. That makes things much easier. So I need to create a patch harness from the Factory ECU to the GM one. are people putting that inside? I saw the Vorshlag kit is putting it where the factory battery goes but I'm not trying to move that. Also do you know if the factory ECU plugs are available so I can pin my own harness? I'll dig around a bit to see if there is anything but I wanted to see if anyone found them already.

You need the FRS ECU in order to run all the amenities. Power Steering, Tach, Speedometer, Fuel level, ABS, AC etc. The new box from MRS lets the ECUs basically talk to each other making alot of that stuff work. So yes, you do need the FRS ECU as well as the GM ECU.

frs can work fine with other engines. all what we need are frs crank single and and temp senser for rpm and heat gauges . but cel will glow up . rpm works and temp works also fans

Wire the GM engine to be like a "standalone" engine in the car and minimize the Subaru wiring.

If you go with my CAN solution, yes, I prefer to leave the factory ECU in the vehicle. It weighs less than a pound, just keep it. It will really only need a few wires going to it to produce all of the signals needed, so if someone would eventually really want to slim down the wiring, it is possible.

Reason for leaving the factory ECU is that we base all of the message timings off of it and it also provides signals for brake input and cruise control buttons.

If you are manually wiring up a crank angle sensor and dual coolant temp sensors for the CAN stuff to work, yes.

My plan is to run both ECU's have the GM computer run the engine but I'm unsure of what I need to hook up between the 2 ecu's if anything. I need to find some factory ECU plugs so that I can make it plug and play and have the ability to utilize the big square plug that's in the engine bay.

AC1 ECM
1 Knock 1 B28
2 VV1+ B26
3(shielded C) Crank position + B16
4 Coolant Temp THW D30
5 Camshaft positon VC B34
6 VSV/MAF E2 D29
7 MAF E2G A29
8 Cam timing Oil 1E D7
9 Ignition 1 D21
10 ignition 4 D8
11 CPC solenoid D11
12 Knock 2 B17
13 VV2+ B15
14(Shielded C) Crank Position - B27
15 EV1+ B14
16 Fuel Pressure PR B9
17 MAF THA A12
18 MAF VG A22
19 OX1B O2 Sensor B1S2 B21
20 Ignition 2 D10
21 E2 O2 Sensor B1S2
22 Oil Pressure
23 VSV Pim B20
24(shielded B) Throttle Body VTA2 D28
25(shielded B) Throttle Body VTA1 D18
26 cam position bank 2 Exhaust (EV2+) B25
27 Oil temp OT D20
28 VSV VC D19
29 A1A+ O2 Sensor B1S1 B19
30 A1A- O2 Sensor B1S1 B18
31 ignition 3 D31
32 Cam timing Oil 1i D17
33 Cam timing Oil 2i D16
34 Ground B2
35 Ground B1
36 Ground D4
37 Ground B3
38(shielded A) Throttle Body M+ D2
39(shielded A) Throttle Body M- D1
40 Ground D3
41 B+ O2 Sensor B1S1
42 Smart Entry
43 Smart Entry
44 Cam timing Oil 2E D5
45 B+ O2 Sensor B1S2
46 HA1A O2 Sensor B1S1 B5
47 HT1B O2 Sensor B1S2 D6
48 EFI Main Relay B+
49 ignition B+
50 AC Clutch
51 injector port 4 D13
52 injector port 3 D32
53 injector port 2 D22
54 injector port 1 D12

Does this list look correct for the AC1 connector in the engine bay? I had to cross reference last night using the service manual and wanted to make sure I have it all correct before I start making a harness. The left set of numbers is the pins on AC1 and the right letter/numbers is for the ECM.

Weapons Grade sells their standalone wiring harness with integration ala carte if interested.


Sent from my iPhone using Tapatalk

Oh I didn't know you could hook them together like that. Good to know, sorry haha!!

Was this confirmed as being correct?

Bump looking for clarity also.

Sent from my SM-G950U using Tapatalk