Mykl

...I'm not talking about compression numbers, boost, power, etc.

I found what could be a good running S4 engine and transmission for $600. A friend of mine had it and didn't tell me about it, apparently he picked it up from somebody for another guy and he got stiffed. So he's stuck with the engine. ECU may be included.

Apparently it came out of an '88 10th AE, not sure what happened to the car.

I'm asking because I'm tossing around the idea of making this thing go in my convertible. ****, $600 for a longblock + tranny is a damn steal.

I found out about it today, I plan on doing a very **** inspection of the engine and tranny.

I can't remember exactly what is required of a n/a to turbo conversion, but I can find out so I don't need that sort of info at the moment. What I do need to know is if I choose to go with this engine (assuming it's good), what problems could I expect to encounter going to a S4 engine to a S5 chassis.

The big problem I forsee is wiring problems. I know in the S4's the dash wiring harness for the n/a doesn't like the engine wiring harness for the Turbo II. Do they both plug into the ECU? ...or do the two attach elsewhere?

Also, how can I identify this engine/tranny? What clues do I need to look for to determin if it's a S4 or a S5?

Pictures would be extremely helpful if you've got some. I'm ready to do that turbo conversion I've always dreamed of. This engine popped up at a perfect time, just trying to figure out if it's too good to be true of if I need to look elsewhere for the parts I'm gonna need.

Thanks all!

Mykl

Do I smell bad?

...or are there no more technical gurus left here?



Time to resub to the eMail lists, those guys know their ****...

fc3s.org

Well, I'm not a guru in my eyes, but here is some info that may be helpful. Here is a basic list of things you will need to do the conversion on a same series car:

TII transmission
TII drive shaft
TII LSD
TII half shafts
TII ECU
TII wiring harness
TII boost sensor
TII clutch and flywheel
TII AFM
TII air bypass valve (BOV)
Boost Gauge

If you are going from a S4 engine into an S5 chassis, then the wiring harness from the dash will not plug into the S4 ECU due to the plug being different

Personally, I have installed a S5 engine into a S4 chassis using an S4 ECU and spliced the wiring harness from the S5 engine side into the S4 ECU side, and it worked fine for 2 years almost. I sold/parted the Project 86 after that, but it was still running great when I sold it.

On the engine, it is easy to determine if it is S4 or S5 at a glance by weather or not the OMP is mechanical or electronic. The eletronic version has wires coming out of the OMP, where as the Mechanical one has a rod that onnets to the TB.

Let me know if you have more questions and I would be happy to try to help.

Mykl

Hell, I knew that....

I'm getting rusty. I haven't had to dig into my car and get dirty in so long I've forgotten everything.

You aren't still in the business of Japanese import engines, are you? If you can get me a good S5 engine I may end up giving you a call.

I know engine swaps aren't exactly bread and butter jobs, but I don't feel like reinventing the wheel.

Thanks!

Mykl

...oh, and I figured the dash harness in my 'vert wouldn't hook up to a S4 ECU, I was just wondering if there were any tricks around it.

What if I completely bypassed the stock ECU thing and went straight to a Haltech? I know jack about stand alone ECU's, would it work?

fc3s.org

Engine swaps to me are quite easy. I did my first one in 18 hours start to finish and it started first try. I did it alone for the most part. Planning is the key to it being successful IMHO. I planned it out for over 6 months buying every part I could think of needing and when it ame time, it went quite well. That was including changing the engine, whole drivetrain, all the wiring, everything.

The Haltech will run any engine you throw in there. If you run the S5 TII EU, then you have to have the S5 front cover and the elec OMP or the ECU will go into limp home mode. That really isn't as hard as you might think. Actually you could do it pretty easily I think.

Yes I still sell the J-Specs and now we are into rebuilds as well

Mykl

While I've helped many others in engine swaps, I've never done one of my own. I think it's about time I humiliate my friends on my bike and in my car.

Last I checked your engines were going for $1000 for S5 and an extra $350 for the gearbox? I'm sure I can track down the rest in preparation.

*EDIT* -- the S5 ECU will plug into a S4 engine wiring harness? Front cover + OMP is no big deal. I'm sure the OMP I've got already will do just fine.

darkwaveboi

how hard is it to get S5 TII engines?

fc3s.org

Yup, prices haven't changed. They come in regularly about every 6-8 weeks. On the next container I have another 20B and 2 13B-RE Cosmo engines I should be getting a few 13BT's as well. It should be here around the end of the month or so. I need my 20B for a display at SevenStock 5 this year

Mykl

*great*

I like the way that sounds, that engines can still be found. I'll start tracking down the rest of the stuff.

...although, I'm going to stick with the stock convertible rear end for now. A custom driveshaft won't cost much, probably less than the costs of shipping a rear end from Lower Slobobia. I'm not looking to make astronomical horsepower figures, so chances are I won't be breaking anything.

...and when it does break, time for a Quaiff.

fc3s.org

I recommend at least an LSD rear end in that puppy. Nobody wants a one-legger TII

I plan to do a conversion to my vert someday. I just can't bring myself to tear into it since it is still such a virgin mechanically

Evil Aviator

http://www.rx-7.cc/TII.html

Mykl

My convertible is already equipped with a limited slip diff. Came stock that way.

No point in changing it out unless I'm actually going to go to a better, stronger unit.

Evil Aviator, thank you. I think I've read that before, and while it has some useful information, the obstacles I'm encountering are not addressed there. But the list provided is very useful.

The Ace

I dont know much about swaps actually (although I've seen a couple being done), but here's my .02 EUR

- I think that one of the engine mounts is slightly different, in that it has to be moved a couple of cm back

- of course the turbo and the control mechanism of it are totally different between S4 and S5, but since you will have the S4 engine as well you are good to go

- indeed, PowerFC, Haltech HKS etc can control any engine you throw at them. You just need the proper wiring diagram, and the proper values to the numerous parameters of these stand-alones. It requires a bit of work to get them to work properly (and controlling all accesorries), but it's worth it. If you need to make such a swap, getting a stand-alone is great because a) you dont have to mess/worry about the differences between the stock ECUs, and b) you have a great basis on which to work, in order to improve performance.

- if you are getting the tranny as well, then you are getting a tranny weaker than that of the S5 TII. Since you have an LSD you should be OK in that department, but I would look into clutch/flywheel and gear if you're planning on improving performance (i.e increasing HP)

So, all-n-all, getting the S4 complete set and a stand-alone, is by far the better choice. Minimum hassle, and -propably- maximum output...

Mykl

That engine mount thing is an odd point that I've never heard of before. I would think that since the engines were so similar (share the same code) that there wouldn't be many major changes, stuff like mounting points.

As for the drivetrain, I'm sure my n/a gearbox could handle the power I'm going for initially until I got my hands on a S5 turbo gearbox. Assuming that I don't beat on it, of course. The stock rear end will hold up, I've never heard of one failing.

The n/a FC's drivegears are regarded as weak, however I've not once heard of a complete mechanical failure in one, just crusty syncros that come with age. It isn't like the WRX, you hear of people breaking those all the time. But like I said, in the years I've been reading forums and e-mail lists I have yet to hear of somebody really break the drive gear on an n/a, but I've never seen anybody really push the limit.

...all that and I'm not a big drag racer, and I know how to shift. I don't have to worry about breaking stuff because I'm not going to be reving it to kingdom come from a stop and popping the clutch. If I go anywhere it'll be to road courses.

Basically what I needed to know when I asked the questions was what wiring problems could arise, they were as I should have thought.

But, I'll see if that engine is good. If it is I'll snag it and shoehorn the puppy in if I have to.

The Ace

Thats why buying a stand-alone (if you can afford it) is a great idea: you dont have to mess with the stock wirings and ECUs, and you get a piece of equipment that you can use on ANY car....

In my book, that is a good investment

Mykl

Yeah, and I kinda think that figuring out how to install a stand-alone would no more of a hastle than figuring out the stock wiring...