MattMikasa

I'll keep it brief since this is my 2nd time writing this up, I pressed backspace while not focused on this text box and my browser deleted my entire post...

Like the thread title says, I am looking to swap my current 87 NA engine to a TII S5. So my questions are about compatibility between parts. The site jdmenginescorp is selling the S5 engine with the transmission. I'll link the details below if it helps, but to make things simpler it comes with everything on the block and down to the exhaust manifold and transmission. I will need the downpipe, and a few others to make it work according to threads I have read.

http://www.jdmenginescorp.com/engine...s5-engine-swap

So my primary concern is mostly about the compatibility of the driveshaft and rear diff, and of the wiring between the ECU and other harness, not the engine harness, I can't recall the name... I read somewhere, (not sure if it was aaroncake, rotaryrez, or some other thread) that I will eventually run into a wiring problem between the cpu and an internal harness, which will result in me keeping most of the NA parts to "trick the engine into believing it is still an s4." The write up listed in the FAQ does not mention this problem, and I am killing myself now trying to find the place I read about it again.

-Guide mentioned https://www.rx7club.com/forum/showthr...threadid=26647

About the driveshaft and rear diff, I did not read anything in the guide about replacing the driveshaft or rear diff, though I read the NA driveshaft can't truly handle the stress of a turbo engine. My concern then is the difference in length and fit between the turbo driveshaft and the the stock LSD in my 87 GXL. My fear is that I will have to replace the shaft, which will then only be compatible with a turbo rear diff, which will then only be compatible with the TII rear axles (I read they are shorter to compensate for a wider TII rear diff).

These are really my 2 biggest concerns, that a seemingly "simple" task will snowball into a complete swap of nearly all the components in my engine/drive train. Thanks in advance for any help, I spend a lot of time reading about projects here and finally decided to do some planning of my own.

HAILERS

The turbo drive shaft rear yoke won't fit the n/a rear end. Different sizes. A driveshaft shop can make you a drive shaft or you can buy one from MAZDATRIX that mates a Turbo transmission to the non turbo rear end.

If you just want more power and are not a *rev to eight grand and dump the clutch person*, then you just need the engine and transmisson with a driveshaft as described above.

For a EM harness, all you need is your stock non turbo harness with MINOR wire adjustments. For a ECU you would need a series four ECU if you want to keep it simple. If you use a series five ECU, it can be done but it takes some know how and I won't get into that because I never did that (never said I couldn't do that). It's a matter of matching wires and plugs a *stuff*. Backwards in my opinion.

Think about it. A series five engine is on the whole the same as a series four. Four injectors........four sparkplugs.......boost sensor.......afm.......water thermo sensor.....air intake sensor.........cas....blah, blah, blah.

You would need a series FOUR afm, boost sensor if you used a series four ECU.

You would also need a turbo transission mount. The non turbo mount won't fit. The transmission you buy might have the mount with it.

What's the difference in hp b/t a turbo and non turbo car???? I don't know. What? twenty hp??? IF the non turbo rear end can't handle that, I give up.

dot_txt

iTrader: (1)

I've been running my TII on a N/A trans + rearend and it has been holding up fine.

Otherwise the N/A rearend will not fit the TII driveshaft.. Nor will the TII trans fit the N/A driveshaft.. You really have to swap the entire system out for the TII system.. Or get a custom driveshaft/one from mazdatrix.

Now I feel I should speak from some level of experience doing JDM swaps into RX7's.. That you may want to reconsider your choice of engine importer. I have never heard anything bad about JDM engines corp, but I have never heard anything good either. I have had enough bad experiences with JDM rotary imports that I would really suggest looking into a better vendor (especially for the price they want). Japan2LA is the only vendor I have heard consistently good things about. Otherwise I have worked on engines from Tiger Japanese, GotJDM, and one other.. and all have had some problem, including the one I put in my car (From Tiger Japanese).. Which ended up costing me a good deal over what I initially paid for the engine and parts. And I consider myself lucky that the problems I had didn't force me to rebuild the engine I received. These engines like to show up blown, or rusted up to hell, and the hassle of the return is ridiculous, when you could order form someone who has a good reputation in the FC community. My recommendation, Send Japan2LA a PM and see what he can do for you about getting the S5 engine. You will likely save yourself a whole lot of hassle.

Now with that being said, heres the link for a guide on how to swap between series on these cars. http://rotaryresurrection.com/2ndgen...o_s4_swap.html

The japanese ECU and harness will do you little to no good as the ECU usually shows up blown, and the harness is too short. You can ebay the turbo harness or just use the N/A harness with some minor modification. Also you will need some S4 TII parts (like the front cover and OMP, all of which are detailed in that guide). Along with this you will need the S4 TII ECU. If you can afford it you could go standalone and bypass some of these problems.

Thats all I can really think of right now.. If you have any other questions.. Just ask. Good luck.

MattMikasa

Thanks for the help, cleared those up for me and now I can continue creating my list of parts etc.

stophie

iTrader: (-1)

sooo... howabouta s5 n/a to t2 swap? is the harness too short because of the right drive shizz? and shouldn't there be a warranty for the brain? and what exactly is the difference between the n/a and t2 rear end (other than the lsd)?