I busted the tail shaft housing on my '85 GSL, also the drive shaft. The trans is on the verge of a rebuild also.
I have a trans from a '90 T2 that I want to instal. I plan on beefing up the car for a T2 swap in the future. So I needed the T2 trans any way. I figured on using the appropriate clutch fly wheel combo and a modded mount.
then I ran into this thread: https://www.rx7club.com/showthread.p...ht=(DRIVETRAIN)

I guess There are more issues. I need to know if any one has over come them? I don't want to mod the Trans because I will need it for the T2 swap.
At the same time I can't wait To just install a T2 motor with it. I need the car running.

Thanks

 

I have never done the swap; however, I think you will need to shorten the drive shaft/ use an s4 N/A flywheel. I do belive the trans. will actually bolt up to the 12a.
Guys, please correct me if I`m wrong.

 

Sa7 That is the info I had going into this. what is throwing me is the starter/Flywheel fitment.

thanks

 

TII tranny needs the matching starter, flywheel and clutch. Lightweight flyweel with the correct 12a counterweight and custom built driveshaft is what works. Whether you move the shifter housing is your option but is highly recommended.

 

it can be done but you need an old school removeable bell housing and a new clutch with TII spline and modified TII to FB driveshaft.

 

Will the T2 fly wheel bolt up?
The fly wheel needs to be light weight?
why do I need the old school bell housing?
I know, Lots of questions. I just have to understand. I don't know any one I'd trust to help so I need to make sure I have the right Ideas.

Thanks

 

None of the stock flywheels are really going to work for you, you'll need the counterweight from an automatic 12a (readily available new from Racing Beat/Mazdatrix) and a lightweight flywheel made for the T2 trans. The stock flywheel is all one piece so you have to go with a lightweight two piece setup for this to work. There may be other options I'm not aware of but this is the route I would take.
The trans should bolt up to the 12a with no problems. If you care at all about the fitment of your interior you'll want to modify the shifter to line up better. The driveshaft needs to be custom made (but will still be usable with your T2 engine, so a good investment) and the trans mount will need to be custom made (has been covered in many threads, and many different ways to do it)
Hope that clears things up a bit....

 

lemme clear this up.

I will answer your questions but before I do, please search on the difference between diameter of a TII flywheel and your flywheel. I'm evil and I like to give people a hard time.

 

I know that my fly wheel is 225mm. And I know that the T2 is larger.
But would the splines match?
As far as the old school bell housing, why. I cant look at my T2 trans right now but weren't they one piece. and Coming from the T2 it should accommodate the t2 fly wheel, right?
ok search function said that T2 fly wheel is 240mm.

 

Ok, I think Wacky has tortued you long enough. There is a lot of missinformation in the search threads so I am going to give you the lay down since I am one of the few that has done this swap and really knows hands on.

You basically have two options-

1. You can use your stock 12a flywheel if it is a 225mm flywheel and pressure plate. But you have to use an old school rx4/cosmo bellhousing and buy a 4 puck clutch disc from RacingBeat that has the TII splines and also you have to use an old school starter. This is how I am running mine in my rx2. This is the only way this combo will work on a 225 mm flywheel setup. Don't let anyone tell you differently because I went down that road and had to find out the hard way myself. Now with this option there is one draw back. When using the old school bellhousing it shifts/tilts the trans to the left/drivers side by about 5 degrees so the shifter will sit pretty close to your right leg. I actually like it because it helps me shift faster.

Ok option 2- Using the TII trans and bellhousing you need to buy an aftermarket lightened TII flywheel- steel or alluminum, such as RB's, and buy the rear counterbalance weight for your year 12a rotating assy, TII clutch and pressure plate and TII starter and TII slave cylinder. This will keep the trans straight up and down, but you have to buy more parts and will be more expensive.

The difference in parts above is that the TII flywheel has a larger diameter flywheel/ring gear. So if you were to bolt the TII trans/bellhousing to your 12a right now the starter will not work and hence the use of either option 1 or 2.

In the use of either option above you will also need to make a new driveshaft and trans mount and crossmember. And if you want the shifter to sit in the stock location you will need to shorten the shifter linkage inside the tailshaft and that is a whole other thread. In either case it is a lot of work, so if you don't have the horsepower to break the stock trans, then just replace the stock trans. as I'm sure you will after reading all this above.

 

no the splines will not match
i think the t2 trans uses 23 spline input shaft thus you need a modified disc sold by RB/mazdatrix

 

Actually I'll probably go with option 2. the amount of work doesn't bother me. I just have to know what the work is. this still leaves one problem though. how do I get the turbo II fly wheel to bolt up. Option 2 was how I envisioned it in my head but I think I'm still missing some thing. It's probably obvious.

thanks

 

The aftermarket TII flywheel will bolt up to the rear counterweight. YOur going to take the stock flywheel off and throw it in the Ocean, then the rear counterweight that you will buy for your rotating assy, will bolt up with the one big flywheel bolt torqued to 300ftlbs, then the TII aftermarket lightened steel or allum. flywheel will bolt on top of the counterbalance and so on.

 

why can't you just put a TII clutch disk on a stock flywheel?

 

do I have to use an counter weight from an automatic?
thanks

 

you really don't need that much trans, save it until you do an engine upgrade and just get another 5 speed from a 12a, glsse, or s4/s5 n/a with you tail swapped on.

 

My tail is toast. have the T2 trans already. will need the other parts for the t2 swap any way. why have 3 trans sitting around. my toasted one my t2 and another fb trans.
car is being prepped for eventual t2 swap any way. I want it drivable in the mean time.

 

Yes, Mazdatrix/Racing Beat sell them new along with the aftermarket lightweight flywheels. Just make sure you get the counterweight for a 12a and the flywheel for a T2. Use a T2 sized clutch setup and off you go.

BTW, while I agree this is more trans than your current setup needs I also think you are being smart in swapping this if you plan to go with a T2 engine later on. Just one less hassle to worry about during the swap.

 

Make sure you get the correct rear counterweight for your year rotors.

 

the list:

'90 TII trans (already have)
'90 TII light weight steel fly wheel
'90 TII clutch
'90 TII pressure plate
'90 TII starter
'90 TII slave cylinder
'90 TII trans mount

'85 GSL moded trans cross member to accept TII mount (already have)
'85 GSL Auto fly wheel counter weight

I have a new '85 drive shaft from MazdaTrix that I was going to have shortened.

deciding If I want to relocate the change lever.

 

You can't just shorten the driveshaft. It needs a TII yoke, which usually leads to a complete shaft due to differences in yoke diameters.

 

and why would you mess with a brand new driveshaft from mazdatrix. sell it instead!!!

 

So I probably wont be able to mod a T2 shaft either?
But I'd need it for the yoke.
The new shaft will have to be totally custom, not just shortened with a new t2 yoke?
So I might have a new '85 shaft for sale soon.

Thanks

 

Search for the thread "chronicles of a T2 swap" there is a link in there where you can get a new driveshaft made with the T2 yoke on the front, GSL flange in the rear and the right length all for about $300.
And no you cannot use a modified T2 driveshaft, its about half as long as you need it to be...

Just searched myself, here is the site to get the driveshaft from: http://www.thrashdriveshaft.com/pro_series_shafts.htm

 

I think that I might fix replace the tail housing and drive until the trans finally conks out. In the mean time Acquire a t2 motor and do the swap all in one go. While honing the suspension as I go.

Thanks

P.S. any one Have a tail shaft housing for an '85 5spd GSL