I'm trying to round up all the parts to do some serious upgrading on my gen2 BRAT. Currently, I'm running an EA81 and the previous owner swapped in a dual range 5 speed. I'm planning on putting in an EJ22 and I'm giving some consideration to putting in a full-time AWD transmission from an RX. I have the EJ swap stuff figured out, but I have some questions about the transmission.

 

Aside from the transmission itself, what else would I need to replace to make this work? I'll have to make sure I have the same final drive ratio in the rear diff, of course, but are the axles the same? Can I use the same driveshaft? Any other considerations I'll need to make while sourcing parts?

 

Thanks!

Yep, rear diff will be different ratio.

 

You'll have to either make hybrid 25-spline EA81 axles, or swap in 23-spline stubs into the transmission (possible, but requires complete disassembly of the transmission).

 

 

 

I would highly recommend against it. I hated that transmission. Very short gearing designed for the turbo, FT4WD center diff sucked in most situations.

 

If you're building a street machine and want AWD, use an EJ transmission. If you're going lifted and want the low range, stick with the PT4WD.

I'm already lifted and I do wheel it some, but realistically it is used 90% street and 10% offroad.

 

I like the idea of FT AWD, but not if it will be unpleasant to drive. Thanks for the input!

Hello jmoss

 

You stated earlier "upgrading my gen2 brat... I'm running an EA81 and the previous owner swapped in a dual range 5 speed."  The original tran was a 4 speed right? 

I'm already lifted and I do wheel it some, but realistically it is used 90% street and 10% offroad.

 

I like the idea of FT AWD, but not if it will be unpleasant to drive. Thanks for the input!

 

With that in mind, I'd look for a 4.111 EJ 5MT. Good gearing for larger tires and mild offroad use, but much better street manners.

 

 

It is a harder install. Transmission mount is different, you'll have to have a driveshaft made, hybrid front axles, some creativity for rear diff (IMHO, easiest to swap an EA carrier into a 4.111 EJ housing and R/P, that way your stock axles will work fine). But you won't need an adapter plate, and you'll have a myriad of clutch options.

With that in mind, I'd look for a 4.111 EJ 5MT. Good gearing for larger tires and mild offroad use, but much better street manners.

 

 

It is a harder install. Transmission mount is different, you'll have to have a driveshaft made, hybrid front axles, some creativity for rear diff (IMHO, easiest to swap an EA carrier into a 4.111 EJ housing and R/P, that way your stock axles will work fine). But you won't need an adapter plate, and you'll have a myriad of clutch options.

I can't imagine wanting AWD that badly. I think you have me convinced to keep my D/R 5spd.

That works too. The FWD is frustrating with EJ torque and EA front suspension geometry...lots of wheel spin. But it is nice while cruising.

Lots of wheel spin. 

 This is my fear. I'm not sure whether to expect it to want to spin every time I take off, or just if I try to take off in a hurry.

 

I imagine it would be horrible on stock sized tires. I'm hoping my 27 inch tires will help keep me grounded.

90-94 legacy 5mt's will be 4.11 final drive and have the stubs in the rear diff. That will be a direct bolt in and allow you to use stock rear axles.

 This is my fear. I'm not sure whether to expect it to want to spin every time I take off, or just if I try to take off in a hurry.

 

I imagine it would be horrible on stock sized tires. I'm hoping my 27 inch tires will help keep me grounded.

 

For just normal street driving, it's livable. But worse than any other FWD car I've ever driven (I've owned 2 EA82s that were FWD/PT4WD and EJ22 at some point, one for about 6 months, and the other for about 2. Both with low-quality all-season stock sized tires). I used 4WD on the street more than a few times on the PT4WD car when I was trying to jump out in traffic or something.

 

Larger tires will certainly help, both in the extra grip from the larger contact patch, and extra inertia. 

Maybe I'll just fill my front tires with sand or anti-freeze to increase inertia 

 

What could go wrong?!