Sam_RX7

iTrader: (1)

Hey Everyone! I need Some help here!

Ive got a 1990 GTUs, I just recently bought a s4 t2 motor. It came with the motor only. No top mount, wiring harness what so ever.. Anyways, i was just wondering will i be able too use any small parts off of my s5. Such as alternator, pulleys, starter, fan etc...

misterstyx69

iTrader: (142)

You have entered the "cluster Fark" zone.
You need to have a way to control an OMP,or delete it.You would be Ideally SET if you would have purchased a S5 TII engine.
So,either you use an S5 Front Cover on the s4 engine or Use a standalone ECU.(the S5 Computer will not allow you to remove the OMP.)
..so..you can use the KEG that you have..put the s5 parts on,use the Injectors,turbo etc..
DO NOT use the S5 flywheel..(it is meant for the S5 Engine) use the S4 flywheel,the one that is on the New engine.The trans and starter,etc are Fine to use.

durtled

well...s4 prolly wasn't the way to go but if its what u could get then thats what we'll make use of. u can use the alt everything else is to much bother. the wiring harness isn't a big deal u need to use the sensors from ur s5 block. if the engine didn't come with a fan i would just efan it. clutch fans are a pain in the ***. i would just buy a intercooler and front mount it. other than that u need a turbo ecu. and the turbo electrics afm boost sensor and so on.

Sam_RX7

iTrader: (1)

I appreciate it very much!
And im sorry for all these questions. I havent been in the rx7 game that long.
But isnt the s4 t2 motor an auto OMP? Is what the guy i bought the motor from told me So basically all i would need is a ECU and a t2 Wiring Harness.

Thanks!

Sam_RX7

iTrader: (1)

Yeah, my car does still have the fan in it. He did give me the stock turbo though i just remembered also the pulleys and starter and thats it that came with the motor.

lunardeathgod

the omp may be auto, but what i can remember is that s5's are electronic?

correct me if im wrong please

Sam_RX7

iTrader: (1)

thats correct i believe.

HAILERS2

Series four OMP are mechanical. They have a bent rod running from the OMP to the throttle body. Move the throttle and the rod pulls up on a lever on the series four OMP to supply more oil to the oil injectors.

Series five OMP are electronic with no bent rod/lever. If the Series five ECU does not see the signal from the series five OMP then after a given time period........the engine goes into LIMP mode. In other words drives crummy.

So you put the series four engine in the series five car with the series five ECU and you now have a problem with the ECU not seeing the signal from the OMP (cause there ain't no signal a'coming from a mechanical pump). You could just pull the OMP from the series five engine and hang it from the harness and then the ECU will see a signal and there will be on LIMP mode.

Or Digital Tuning has a ECU fix for your situation. It fakes out the OMP signal so the limp mode does not happen. Cost?? I don't know. Visit their site and see. If you go that way, then you can leave the series four's mechanical pump as is on the engine and it'll take care of the oil supply to the injectors.

You NEED to use the series five EM harness on the series four engine your putting in the car. Do NOT use the series four EM harness. Won't mate with the series five's Front harness to the ECU.

Sam_RX7

iTrader: (1)

thanks for all the help guys! Is there anything else i need too know before i do this transplant?

HAILERS2

If it was a series four...........you'd have an issue with the flywheel/transmission working with the turbo engine if you going to use the non turbo transmission.

I'm assuming you have a non turbo car right now and only have a turbo engine withoout a turbo transmission.

On a series four the non turbo starter will not mate with a turbo flywheel. Then if you present car is non turbo........gotta get a turbo exhaust manifold and things along that line of thought.

Nobody likes talking about swaps because it's been ground into the dirt on this forum and the old swap threads can be looked at doing a search on the search engine.

Gotta have a turbo inlet duct and the like for it to work.

RotaryRocket88

iTrader: (7)

Lots of info in the FAQ: https://www.rx7club.com/showthread.p...55#post5131155. I added the thread in my sig. awhile ago, and there is a link to rotary resurrection's tech section which goes over some issues swapping between series. My advice is generally don't do it. But if you really want to, it's easiest if you use all sensors/ECU/wiring from the same series, and don't try to mix and match anything.