S4 TII swap into an s4 chassis
 

just a few quick questions. im swaping a whole TII s4 swap into my n/a 88 rx7,and i just wanted to know the level of difficulty i might get myself into. i assume its just unplug. remove. install replug. but i was wondering about the electronic side of things. i plan on upgrading the turbo later so what type of boost controller/ aftermarket components should i be lookin @?

I have just gone through this with some bloke on another rotary forum.

All the wiring is totally different. So you are going to need ALL of the turbo wiring looms, dash and ECU's
If your going with the turbo gearbox, your going to need either a custom tail shaft, or the turbo diff. Im not 100% If the half shafts are different, i do know that you cant swap ABS and non ABS half shafts.

Unless you can do all the wiring yourself, it may just be cheaper to sell the NA and buy a turbo...

na halfshafts will not bolt up to a turbo diff. However you can get the t2 driveshaft to fit a na diff. Slot the 4 bolt holes with a grinder, and done.

As far as s4 to s4 swap,it is really simple. You keep the same dash harness and driverside harness. The only thing you swap the the engine,drivetrain, and ecu. s4t2 engine harness plugs right into the s4 na dash harness

use your n/a harness if the turbo motor is the same series which it looks like it is. heres a thread, please read through it all.
https://www.rx7club.com/2nd-gen-archive-72/s4-na-turbo-swap-details-813825/

there you go! :) you'll want to get a turbo2 rear end if you plan on drifting or hard launches a lot. mazdatrix sells a t2 trans>na rear end drive shaft or you could take your shaft to a shop and have one made. dkwasherexd's method can work but its at your discretion. na rear with t2 power isn't a good idea for beating on the car so you've been warned. if its just a daily with some spirited drivng, might be ok.

i get what your saying. but what im getting is the whole engine,trans,wiring harness, and what i wanted to know is if it will all pug into the cpu nd stuff. i know ill have to get a boost gauge obviously.lol

I got it a bit wrong - if your swapping S4 for S4, or S5 for S5 then you'll be fine - it should all just plug in to the ECU's.
Your going to need the stock Turbo ECU - but you can keep the NA BCM (body control module, not sure what you call them, but they run the idiot lights, interior light, stuff like that)

Its swapping S4 with S5 and visa versa that's problematic.


Oh, your going to want to swap out the rear end with the turbo stuff - NA single spinner diff is going to explode if you have some grip ;)

Just did a s4 turbo swap and left the na tranny driveline and dif in. I'll let you know how long it last. If you use the turbo tranny your going to need a turbo driveline and dif. Someone makes a driveline that is turbo to na think it's corksport. Otherwise you haveto use your na tranny.

TII emissions harness will NOT plug in to n/a dash harness without mods. Search its been covered. Particularly in depth by HAILERS. the easiest solution is to swap the na harness onto the too engine, extend the tps and bac wires and there are 2 wires at the ecu that are different. 1 runs the p/s switch the other is knock sensor input from the knock box. Download the factory service manual available in the faq section because I can't remember which 2 wires they are. (I believe 1R is one I wanna say 1K is the second but its been a few years so check for yourself). Your gonna need the turbo model maf and pressure sensor. It'll run fine without the knock box and you will have to just cut the ps switch wire no biggie if your dropping emissions. I believe that the ps switch wire runs like the twin scroll valve or something and can be rewired to the appropriate solenoid as well as rewiring of the knock box if you'd like to retain that feature as well.
Swapping all the drivetrain is obviously recommended and it all bolts in but you will need the trans, diff, driveshaft and halfshafts. The exhaust is different but manageable. The clutch slave and soft line I beloved are different also (I know the slave is and I believe so is the line if memory serves me correct). Add an aftermarket boost gauge it'll be better anyway. And last is the intercooler. You NEED a way to cool it. Either stock turbo hood, cutting up your na hood and outfitting it with a similar scoop as stock (remember the square inches of the opening should be at least 1/3 the surface area of the cooler for proper cooling) or a front mount from the get go.