Yeah ITB's require a lot of tuning and are very fickle. The tune will need to be tweaked every time the weather changes much. For reliability stay stock.

 

I have the engine harness and ECU but we're not using stock gauges or ignition switch or anything. It's do-able, I was just looking for the easy way out. And I like the look of ITB's.

 

So I did an s2000 engine swap and kept the stock intake mani (for now)

the wiring is really pretty lightweight. If you want to stay with the stock ECU you need the key and key transponder (either used for ignition or taped together and stuffed under the dash)

If you decide to go to the haltech PNP for ease of running/tuning/logging (like I did) then you plug in the two engine harness plugs into the ecu and you have to cut and splice a few wires on the 3rd engine harness plug to get the car all the way sorted. Most of this stuff is things to get the VSS signal to the ECU or to get the alternator charging.

From a wiring perspective below should be enough to get the engine running happily with the stock management or the haltech PNP - this is my additions from a few diagrams I found around as I connected a few more things than most people do.

connectors to potentially worry about on ECU

A15 immo fuel pump relay - goes to fuel pump relay to enable fuel pump - fuel pump relay output - you can delete the IMO by going around this
a20 rad fan control - goes to fan relay to enable fan
a24 start switch signal - to starter motor switch
a32 brake pedal position switch - normally open

C101 connector
1 - ignition system BLK/YEL +12v - connect to the ignition key
--2- Air conditioning- not connected
3- starter motor -BLK/WHT- +12v through starter motor switch
4- YEL/BLK +12v from ignition switch- power supply to ECM
5 -BLK/YEL +12v lambda sensor - connect to ignition key - I run a wideband so I don't use this
--6- YEL/BLU air pump - not connected if you do not use air pump
7- WHT/BLU - alternator light(on the dashboard) required to get charge!
8- BLU/WHT - VSS sensor connected probably to the speedo gauge - must loop back to ecu A9
--9- YEL/RED - low pressure warning light(on the dashboard)
10- WHT/RED +12v ECM/ immobilizer light - hot at all times
--11- YEL DRL indicator light- probably check engine light but not sure- in my car it is not connected
--12- GRN/YEL - not connected
--13 - WHT/BLK - secondary air injection system- not connected
14 - BLK- ground
--15 -BRN/YEL - DATA LINK CONNECTOR - this is only one of few wires that go to data link connector- rest is probably in the ECU 32P socket.
--16- GRN/YEL air pump - not connected


My recommendation on ALL engine swaps is to get it in, running & sort out all the little issues with it as stock as possible. THEN you can start adding the fun parts. stock always works better - chasing wiring issues down (as you always have to in a swap car) is MUCH easier when you can read through the stock wiring diagrams (let me know if you need a copy of those, I have all of them)

the stock s2k harness is almost a stand alone engine harness as is which makes it go pretty fast - if you'e familiar it's about on par with an LS engine swap harness - minus the ease of stock ECU tuning.

 

Hi I'm a noob to the S2000 forums. Great info! I'm just starting a project to put this drivetrain into a Triumph Tr4. I had some of the same questions. Conventional wisdom seems to be keep it stock, and that seems prudent. Thanks

Rod H