I'll be looking at changing the box on MY94 WRX soon because of selector problems.
The car has front and rear CUSCO limited slip diffs fitted.

Now this is what I'm not sure of, if I fit the box i have sitting in my garage (which has the normal WRX diff in it), would I have to change the rear diff to a normal one to match the front diff??

Gearbox is the same number as whats currently in the car.

Any help much appreciated.

Mike.

 

Mike i'm guessing you dont know the ratio of the cusco diffs??

It will also help if you post the gearbox codes please mate.

 

You would have hoped whoever fitted the Cusco diffs would have used the OE CWP, so you should be alright...

Best way to check is to take off the rear diff, then spin the propshaft flange and count how may full revolutions it takes to spin the driveshaft sockets 1 full turn. This will give you your ratio. Since yours is an impoert WRX the front diff will be the same ratio as the rear. Then you can compare that to the one in your garage.

 

The box code is TY752VB3FA (same as what's in the car now). The Diffs were fitted in Japan, they're quite tight too!
Thats all I know about them without stripping them out.

So really, the best thing i can do is work out the ratio off the rear diff.
What should it be to match up with this box?

 

That box is from a MY95WRX, 4.111 diffs front and rear.

In fact thinking about it, you can just jack up the rear of the car, unbolt the prop, then count how many turns the prop flange does to one full rev of the rear wheel.