I just picked up an 89 gxl and i'm interested in doing a s5 T2 swap. I just picked up a s5 jdm motor that comes with jdm ecu. I've upgraded the rear diff to a clutch-type lsd and plan to swap the flywheel off my na to the t2 and run my current tranny set-up. I'm also guessing a fuel upgrade will be needed? I've done quite a bit of research on here and have found that I can use my NA wiring harness on this motor but I've also found that using this harness on a jdm ecu can have issues. Alot of the info given here is for the S4 swap but not much info for the s5 swap. What exactly do I need to do to the Na harness to adapt to the jdm t2 motor? Also do I need a us spec t2 ecu to make things run properly or will the Jdm ecu work fine? Also can I get the jdm ecu modded to work and where and who does that? Also any help with other issues I might run into would be greatly appreciated. Thanks,
Ira

 

S5 NA to S5 TII

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Quote:
Originally Posted by Rx7_boss
wiring ???? i am swapping my 91 is the harness on the passenger side firewall the only one i dont need and when i put the s5 t2 harness in is there any modding necicary for that too work with my car??

The details in the first post of the thread are for S4 swaps. And don't swap in the TII harness. You'll just be wasting your time not adapting the NA harness. Like S4 swaps, the S5 NA harness easily adapts to the S5 TII engine.

********************* FOR S5 SWAPS ONLY ***********************

When using the S5 NA EM harness:

1) Plug 6PI connector into turbo duty solenoid (ECU pin 3R)
2) Cut VDI plug off and connect ECU-side wire (Y/B) to knock sensor (ECU pin 2M)

Other than that, it's basically the exact same procedure (with the S5 electronics) as is outlined in the first post of this thread. The only real exception is that the N370 US-spec ECU should be used, or a chipped N374 J-spec ECU. The stock N374s have a history of not firing the injectors properly when mated to US-spec wiring.


Awesome post thanks brother............... If I'm going to run a fairly stock set-up any recommendation on where to get the n374 modded.

 

You say a chipped n374 will work. I've looked at r-tek and they only have a stage 2 upgrade for the n374. Any other companies that can do a milder tune on the 374 to make it work with my na harness?

 

N374 is a j-spec ECU. The chipped versions come from Japan only.

I would suggest a US-spec N370.

 

I talked to mike at rtek this morning and he said there stage 1 ecu upgrade to the n374 should do the trick. Finding a n370 seems to be an impossible task these days.

 

Interesting. On the site they don't list the 1.x chips an option for the N374: http://www.pocketlogger.com/index.ph...age=1&ecu=S5T2.

 

I saw that and thats why I called to ask. He said they do all stage1 upgrades on both ecu's (n370/n374) they just haven't changed it on the webpage.