Along with my USDM Sti motor swap I was interested in getting a 6spd trany installed in my 98RS. I was originally told that all I would need is the appropriate final drive LSD R180 and to shorten my prop shaft with an auto wrx drive shaft.
Is this all I need to do to match up the trany/ diff with my rear end??


Or, along with the Sti LSD do I need the new axels, hubs, knuckles, brakes, etc.. to make it fit correctly??

Thanks again.

Mike D.

It looks like you are confusing the two different ways of doing it.

If you use the R180 you will have to get new rear axles, hubs, and brakes. But you will not have to change the final drive. (more than likely make sure you know what came off which car)

If you use the r160 you will have to change the ring/pinion to make it a 3.9. (more than likely a 3.9) But you can keep your 98RS axles, hubs and rear brakes.

You can also get the r180 and buy driveshaft shop axles that adapt from the r180 diff to the r160 hubs. So you'd keep your hubs and rear brakes.

Louis

exactly what he said ^^^^^^^^

Thanks for clearing things up-

Anyone have some personal experience knowing which method is most practical/ cost efficient??

I’m getting all the parts from FourStarMotorsports and RalliSpec is doing this install so I know I should be in good hands. Four Star said they would basically give me the R180 and if I’m not mistaken it’s a lot stronger that the R160. Where can I find custom axles to match my hubs w/ the R180?

Also how difficult would it be to change the final drive to 3.9? is it worth the trouble & $$ with these other 2 options?

Thanks again guys,

Mike D.

It looks like you are confusing the two different ways of doing it.

If you use the R180 you will have to get new rear axles, hubs, and brakes. But you will not have to change the final drive. (more than likely make sure you know what came off which car)

If you use the r160 you will have to change the ring/pinion to make it a 3.9. (more than likely a 3.9) But you can keep your 98RS axles, hubs and rear brakes.

You can also get the r180 and buy driveshaft shop axles that adapt from the r180 diff to the r160 hubs. So you'd keep your hubs and rear brakes.

Louis

i did that before keeping the 6spd with the rear R160 setup and i destoryed the rear diff. but i was racing my car at that time. doing this is like installing a AE86 rear diff on a skyline or 300zx. they will break!

It looks like you are confusing the two different ways of doing it.

If you use the R180 you will have to get new rear axles, hubs, and brakes. But you will not have to change the final drive. (more than likely make sure you know what came off which car)

If you use the r160 you will have to change the ring/pinion to make it a 3.9. (more than likely a 3.9) But you can keep your 98RS axles, hubs and rear brakes.

You can also get the r180 and buy driveshaft shop axles that adapt from the r180 diff to the r160 hubs. So you'd keep your hubs and rear brakes.

Louis

Louis,

You do realize you're talking to the kid who bought his Forester motor from Gruppe S and kept coming to check out your car in the garage :p

Mike,

Get a R180 along with the whole rear subframe and stop being cheap. Do it right once :D

You're going to need good brakes to stop that bad boy and if you get a whole rear subframe it will include Brembos and they should be enough. Stop being cheap or you're going to end up in a lake again :p

If you're going to be cheap, take the rear end out of that Outback wagon because I'm pretty sure it's 3.90. Somebody correct me if I'm wrong...

So theres no way i can use my non LSD axles with a rear LSD ??

If I get the whole rear subframe with brakes, my offset is different from the Sti so it wont match the hubs,correct? plus dont they only fit with 17in rims?

what are some other options ppl ?

Anyone know where I can find custom Axles to fit my rear end and match up with the R180??

Seriously... if you don't plan on squeezing more than 500 whp outta your setup, you should just stick with the R-160 and just switch the ring and pinion... it is cheaper and you really don't need the R-180.

If you use the r160 you will have to change the ring/pinion to make it a 3.9. (more than likely a 3.9) But you can keep your 98RS axles, hubs and rear brakes.

Do you really want to change all of these components just to have a R-180 unnecessarily?

If you deside to go with the 3.9 ring and pinion, let me know, I have a set from a turbo Legacy.

So this would be the easiest way to match everything up? I only planed on doing basic mods, TBE. Nothing to crazy. I just want something that’s reliable and can take a beating of need be. That’s why I changed my mind about using my stock 5spd.

You're going to need good brakes to stop that bad boy and if you get a whole rear subframe it will include Brembos and they should be enough.

Once I get everything in the car and stable than I will start to worry about stopping power.