Airceo13

hey guys, so i have 86 gxl and im planning on swaping a TII motor in it... i have been reading and ive read that i cant use the jdm spec harness? can i use the n/a harness for the TII motor? or is it still possible to make the jdm spec harness work? well i hope you guys can help

RX7freak08

NO I'm pretty sure you can't because the T2 I bet has more sensors then the n/a and you wont have a connection to it.

HAILERS

Yes, use the non turbo harness and NEVER use the turboIIor JSPEC harness on YOUR 1986 non turbo car.

There are too many wires to be exchanged b/t plugs on the harness if you use a Turboii harness on a series four non turbo car with turbo engine.

walken

iTrader: (6)

I've seen a JDM harness work and one that had completely different connectors after the firewall. your n/a harness will work fine if you match injector impedance. if not you only had to wire in some resistors.

HAILERS

A turboII and or JDM right hand EM harness will work but only IF you make the wire changes required. Hope I didn't leave the impression they would not work at all. Just clearing up my remark above. You could even use a series five EM harness if you wanted to make the required harness wiring changes.

But using a n/a harness requires only one to two wiring changes.

dizflyaznboi

Sorry to thread jack but I put a s5 jspec into my s5 na. The swap went smoothly and i used the jspec harness. But no wires for the wipers. I got the plug for the wiper motor to the cpu, that goes through the firewall.

I removed all the wires that didnt go to the wiper motor, and i unplugged the one for the jspec harnesss and plug the wipers in and the motor woudlnt start, and the wipers still didnt work.

If someone could post a link to a thread with the diagrams i need, becuase in the service manual it doesnt have the jspec wiring dirgrams.

Airceo13

so the n/a harness is basically a plug and play? oh and which two wires do i need to change?

NZConvertible

If you don't know, don't post. Don't bet either...

Using the existing Emissions harness is by far the easiest way when putting a Turbo engine into an NA. The Turbo ECU plugs straight an and only requires a couple of minor wiring changes at the ECU plugs. All of the input and output devices are in the same place except for the BAC and AWS valves, solved by simply extending the wiring. You also need to swap the NA MAP sensor and AFM for Turbo ones.

NZConvertible

For S4:

Pin 1R (LG/B wire) is the knock control unit on Turbos and the power steering pressure switch on NA's. If you're installing the Turbo knock control unit you'll need to cut the wire ~6" from the ECU connector and extend the connector side to where you've installed the knock control unit (which also needs power and ground connections). If you're not installing the knock control unit and you have power steering you'll need to cut the wire anyway, otherwise every time you turned the wheel the ECU would get what it thinks is a knock signal and retard the ignition timing.

Pin 2K (L/B wire) is the twin-scroll solenoid valve on turbos and the split air solenoid valve on NA's. If you're keeping the twin-scroll control system operative you'll need to connect the split air solenoid valve connector to the twin-scroll solenoid valve. If you're not keeping the system operative you can leave it disconnected.

HAILERS

If you had used a truboII EM harness in a series four non turbo, you'd right away LOSE the alternators plug that has two wires. On a TURBO car that alt plug is a part of the ENGINE harness whereas on a non turbo it's part of the EM harness. So, right away you'd have to wire in two wires automatcially.

Then, if you look at the two plugs on the EM harness that mate with the n/a Front harness, you'd see that there are numerous wires in the turbo EM harness that don't mate with the proper wires in the non turbo Front harness. So you'd need to address those wires also and move them around. Those plugs are called FEM-01 and FEM-02 in the 88FSM that is downloadable online from this site.

And like the fellow in one of the above posts mentioned, if you used a JSPEC right hand drive EM harness, you'd have to buy a spool of wire to wire in the wiper motor because the wiper wires are not included in the JSPEC harness.

I attach two jpgs of the plugs I mentioned above that mate the Front harness with the EM harness. Look at the jpg. See at the top where they show you that where you see ( ) that that wire socket uses a different wire than the non turbo??? Yes. Count the ( ). Quite a few of *peculiar* wiring differences.

The two that would bother me are the BrR and the BrB. The BrR if left alone will allow 12vdc from the engine fuse to go directly to pin 2B the boost pressue sensor input. A pin that normally never sees more than 3.65 vdc or there abouts. Not favorable. Plus the yellow white that supply the water temperature from the sender to the gauge. If left alone, the water temp gauge won't work. There's others amiss as you can see.

I'm hardheaded about calling the Engine harness the engine harness and the Emissions harness the emissions harness (EM) Sorry 'bout that. The EM harness is the one that has fuel injectors, boost sensor, afm etc. The Engine harness lays on the left side of the engine bay.

HAILERS

And MY opinion about the Knock sensor and the knock box. I ran for quite some time without a knock box for the knock box. Finally I came across one and installed it. I did have to run a couple of wires. LIke a gnd wire which is no big deal , 12vdc to power it which is no big deal since there is 12vdc coming in a wire on the ECU to pick off and a wire from the box to a pin on the ECU. Ran like that for a year or so and came to the conclusion............it's useless. So I removed it. Have not blown a engine due to knock ever.

Yes, if you installed a na EM harness on a tubo engine and did NOTHING to the harness the engine would start up and drive down the street/hwy. Making the twin scroll solenoid work as NZ described above would now give you a twin scroll that WILL make the turbo spool a little sooner than if you had no twin scroll.

Lengthening the bacs two wires so they will reach over and connect to the bac that is NOW on the right side of the engine instead of the left as on a non turbo, will give you an engine that holds an idle. Just make two wires longer, no big deal.

toplessFC3Sman

iTrader: (1)

and if you're already extending wires, the ones to the TPS could be about 2 or 3 inches longer, cause altho it does fit as is, its very tight

HAILERS

Thanks for reminding me. I extended mine but others say it didn't need to be extended. Always wondered about that. Never seen anybody elses car.

Airceo13

wow lots of really useful information!! thanks guys, i'll let you guys know how the swap goes within a couple of weeks