Just wondering if someone can tell me if I can use a TII rear end in my 80SA TII swap? I know anything can work with enough money and time, but I'm wondering if anyone has done this before? I have an LSB with disc brakes from an 83FB, but I'm wondering if using a TII rear would be benificial to me or not?

 

Nope!

 

Wow people really enjoy asking the same questions over and over. It would take a crazy amount of fab would to get the rear subframe differential, axles and everything to sit properly and is not worth the effort. Can't just bolt up a rear subframe on a vehicle with a solid rear axle, and even if you could the suspension geometery is completely different.

Most realistic rear end swap is the ford 8.8", check out Grannysspeedshop.com for more information on it. Expect to be paying $$$, think my rear end 4.33 gears(deluxe kit) heim links (watts linkage and trailing arms), smaller spring option, driveshaft loop, custom length driveshaft, ended up being about $3000 dollars total.

 

Also forgot to mention that the $3k does not include the rear brakes, and I would consider, upgrading the rear brakes and think about going with the 5x4.5 bolt pattern. Expensive as hell, but this kind of rear end setup should handle anything a rotary puts out with ease. Even with the torque of a V8 it will take a beating.

The ford 9" is another option, it is stronger than the 8.8", and the pinion gear is straddle mounted rather than being overhung. Basically a bulletproof rear end, but it weighs a considerable amount more than the 8.8". Therefore I would say it's not really better for our cars obviousily it's in your best interests to keep the weight down.

Here is what the grannys setup looks like (my car):



GSS also offers a "do it yourself" style kit. It would involve you finding your own donor differential, shortening it down to your desired width, than welding the brackets on. Personally I wouldn't go this route unless you have access and knowledge with alot of fabrication equiptment. GSS has a jig that they are able to get everything perfect with, it gets done right the first time.

Hope that helps.
Dan

 

Whats wrong with the stock axle? Is it not sufficient up to "X" number of Horsepower/ torque?

 

The stock rear end will not stand up to big sticky tires, high horsepower and launching the car. People have mentioned levels they think the stock rear end can handle, I perfer not to do so. Basically a rear end is going to go depending on how it is treated, not on an exact hp number.

I am sure you could have 300 hp and be very gentle with it and have good luck. But if you are planning on making the thing take some serious abuse you should think about upgrading.

 

I wasn't talking to you Dan, your're going all out with your build, and need a beefy axle to handle the power your gonna be putting down.

I was talking to the creator of this thread. Unless he has big plans for his RX-7, his stock axle should be more than sufficient.

 

First,

what are your goals, why the TII rear end?

Handling? ie: IRS for handling purposes?

or

HP? Drag racing?

if for HP and drag racing go with the grannies setup like Dan suggested, its about the best option for an FB and 99% of the headaches have been ironed out already.

if its handling and IRS you are looking for, the TII rear suspension is a poor choice, it tends to brake jack due to the trailing arm design.

instead look at a miata rear IRS assembly. their is a writeup on a miata swap that was being done by '85 GSL 302. he is useing a 302 small block with a miata rear axle and some custom fabbing. check out this thread

https://www.rx7club.com/showthread.p...ght=road+racer

I currently time attack and road race my 1st gen here in Japan, and the stock rearend is holding up fine with about 400 at the rear wheels. I do have to watch my diff temps though as they tend to shoot up under prolonged abuse.

incidentally, just because certain members have been there and done that does not give them permission to act like the are from the 2nd gen section.

Kenn

 

I have posted a pic of a 1st gen with IRS.

This said, why bother? unless you are going offroad a solid rear end can be every bit as competent on any flat surface, its all in the tuning, spend the $ on a proper 5 link rear end, spring, shocks and tires and you wont be disappointed

Steve

 

No that looks like it took some effort.

Kenn

 

After you make all the changes to the body and make new mounts its a complete bolt in!

 

Damn haven't seen that yellow picture in years! iirc that was a FD setup he used.