i have a 1987 na sport, bad motor so i bought jdm turbo complete swap. the problem is i think its s5 not s4 the ecu is n374 everything was good except oil pan dented.ive got my engine out along with wiring.the ecu plugs from the na are 2 yellow plugs the third yell plug does not run with the other two it goes back under the dash toward the drivers side.and the plug will not fit the turbo ecu.i hoped i wouldnt have to cut and splice ,ill do what i have to do any help will be appreciated

 

lots of info searching about this topic. It is worth the wait sending it back and getting the s4 you ordered.

john ny

 

if there is anyway i can make it work , im willing to try

 

did you get the t2 wire harness or are you trying to use the na harness?

 

if its a series swap like you said, your in for a pain in the assssssss. i put an s5 turbo motor in my s4 n/a and tried using the turbo ecu instead of stand alone.
i had to get a new Front cover, Throttle body, ecu, fuel pump, omp cause its a different series, oil return tube, fabricated OMP pull line, spliced a shitload of wires. had to get a s4 turbo afm, boost pressure sensor. Its probably gonna run pretty rough, mine certainly did, thats why i went standalone. Your gonna be spending a shitload of money for the series swap, i recommend going standalone, the swap will cost about as much as a stand alone, so just go haltech. Trust me from experience and taking my car to different shops cause of problems, go STANDALONE. make your own harness with the standalone and no wires will show, itll look super clean not to mention you can just drop that bitch in. go haltech e6k.

 

i got everything wiring harness,ecu trans, it would be a lot of trouble to send back and why cant na ecu be used,just curious.stand alone is that aftermarket ecu and how much

 

most of the wires on the engine look like i could replace a few plugs,and use na wires,but then none would plug into turbo ecu

 

you cant just swap everything over..
and you cant use the n/a ecu because the turbo ecu has different operations for the turbo, not to mention when you change series.
series 4 motor has lower compression and creates less boost then a series 5 motor.
the omp on the series 5 is all electronic when the series 4 is oil injection. all in all way different.

if you swap the series 5 motor into a series 4 car you also have to bypass the resistor because of the high impedance injectors that the series 5 motor has. the computer will just tell the injectors to shutoff if you mix and match injectors with a different series ecu.
all in all the ecu has everythinggggggg to do with the motor. you have to get the same turbo series ECU for the same series car. for instance the turbo s4 ecus are n332 and n333.

never try talking to someone who has never done this swap. Ive learned they have no idea what there talking about and many times i have had misleading information. If you want some real info on it you can call me for all the info. ill giv you my number if you want.

Ive done this swap personally and even though im just a kid i know my **** not to bragg lol. But I highly highly highly recommend going standalone. Especially with a series swap because its hard for the series 4 ecu to keep up with the higher compression and more boosted s5 motor. More then likely youll blow your engine. i went to a shop once and there was 3 cars that did the series swap sitting which had all blown there motors within 3 months because the ecu just wasnt enough.

you can get an e6k haltech ecu with the harness you make your self and all the needed sensors for like 1400$. TRUUUUSTTT me the series swap will cost a little more then half that and will not run near as good as it does with a haltech and not to mention youll get way better gas mileage from the tuning.

youll save time and money if you go standalone. but if you wish to go stock ecu go fo it, youll just kick yourself later.

 

check to see if the motor you got indeed was an s5. most JDM motors are. The OMP should be electronic, if you need pics of the OMP ill hook you up in case you dont know what it is. also the OIL filler neck should extend out.

 

and by the way YES i am still using my N/a harness, i just have a plu and play haltech e8

 

the oil filler neck does extend out.could i repin the na plugs to fit the n374 ecu,also there is a black box conn on the side of the ecu no idea what it is.i may go haltech and use my na wiring,also thanks for any help im by myself on this one

 

whats a front cover swap

 

alright....
the n374 ecu is for an s5 turbo. it will not work in your car since it is an s4 car.
unless you use the comlpete s5 turbo wiring harness and yank out your dash and replace the dash harness with an s5 harness, then again that is a hugeeeeeee bitch.

your trying to mate two completely different things together and it will just not work out. But i will give you a little step by step to help you out.
alright.

the front cover is the cover on the front of the block that the OMP and turbo return line bolt to.
to do a series turbo swap like the one you need to do you have to

1. Buy a s4 turbo series
-front cover
-throttle body
-Omp
-Omp line
-oil return line for turbo
-Boost pressure sensor
-Air Flow Meter
-ECU
-Fuel pump
-TPS
-Turbo conversion driveshaft
youll also have to Bypass your selonid resistor since your injectors are s5
splice your tps
splice your BAC
I took off my emissions, if you which to keep yours its a hell of alot more work, cant help you out there.

that black box is a solenoid which acts like a trigger and if not wired right or not the same series the symptoms will be like your afm is cutting out and the engine will start up but die.
theres a decent mount im probably forgetting since i did the swap almost half a year ago, but its a bitch of a swap..

orrrrrrrrrr
you can buy a standalone and just bolt your engine to your mounts and start it up...lol by the time you look at how much the parts i listed are, you gonna shat your pants

 

basically all the new sensors your adding, your gonna have to splice new wire in.

 

+1 on a stand alone.

 

just curious. i was told i had a s5 motor in my s4 TII. Myersprostatus said the oil filler neck should stick out. Im pretty sure they all stick up. do u have anypicks of the differences and easy ways to pinpoint which series it is?

 

man thanks, decisions to be made,first thing is to call the mf i got it from and see what he can do.woud you have to remove all the wires behind dash or just the one to the ecu

 

yup call him and get a series 4. Or you are gonna be a while with the swap. When you get the s4 engine pm me, i have done this swap using th na wiring harness. It was very easy thanks to hailers and nz.

john ny

 

if i get a haltech, can i really just hook it up and run

 

On a series five, the KNOCK sensor screws into the rotor housing. Into a hole just above the sparkplug hole. Rear, I think.

ON a series four, the knock sensor screws into the imtermediate housing, NOT the rotor housings.

Series five EM harnesses won't connect to the series four FRONT harness. A couple of people have managed to splice the right wires b/t those harness to make it work. One lives in the Caribbean (sp?)and the other in the Czech Republic. His name is LUCIU$, I think, and he Answered a thread on this a couple of yrs ago on this site. A sort of how to answer.

Somewhere in this thread: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s4-na-s5-jdm-turbo-conversion-405617/ and you HAVE to know RX terminology to understand what he is writting about. That can be aquired by looking at series five and series four wiring diagrams that are free and online for downloading. DONE

 

that was a good thread might can do the plug switch,also can s5 motor work with na s4 trans

 

before you bother with any of this, remove the exhaust manifold and inspect the rotors and turn the engine to check compression.

 

already did that ,compression good

 

im pretty sre you can use the n/a trans but why? when you have the turbo trans. the trans was the easiest part of the swap i think i spliced like 3 wires on the trans.

if you go haltech you can only hook it up and run if the sensors and wires are already spliced for an s4 car. For example I spliced all the wires from my s4 n/a harness onto the s5 sensors needed for the car. so I just bought a haltech for an s4 and plugged it in. injectors dont matter, they determine that during tuning.

If i was you i would just buy the haltech e6k kit and make my own harness with the wiring they give you. its not that difficult and would probabaly take as long as it would splicing and mix and matching all the different series sensors together.

if you make your own harness with the haltech wiring you can use all the sensors the s5 motor came with. cant get any easier then that.

just check your OMP to determine what series it is. the s5 one is electrical and is a black box. the s4 one is all oil injection.

and to answer your question about the dash harness. If you wanted to use your s5 ecu, yes you would have to replace everything with s5, it would take you foreverrrrrrr. please dont do that..lol

i had the same mindset but then when i actually broke everything down i said fck it and went out and bought a haltech. then i removed everything, bought a front mount intercooler, and all the ther goodies .

PS, i have alot of extra turbo parts that i can sell to you .
i have a turbo AFM just sitting which you will need and a boost pressure sensor thats kinda apoxied together but gets the job done.

 

oh and by the way the plug and play ecu for the frankenstein wiring such as mine would be the Haltech E8. you also have to purchase the halteh pressure sensor and temp sensor which allows you to remove the AFM.