Austrian Impreza

iTrader: (9)

I wonder if itīs possible to swap the internals of a R180 big diff from a 6 speeder STI into a R160 rear diff out of a classic MY97-00?!?
Or what other ways are to make the 6 speeder work in a classic WRX?
I think itīs also not possible only to change the driveshaft incl. brakes, there is more to do, isnīt it?!
Many thanks for your answers!
Greets from Vienna
Markus

Austrian Impreza

iTrader: (9)

Now I went through some pages and had to see that the UK 6 speeders are 1:1.1 ratios and have a 3.9 diff in the front, that means I would have to use a 3.54 diff in the rear.
Can anyone tell me whatīs right, I always had to believe they are all 1:1 with 3.9 ratio front and rear...

Austrian Impreza

iTrader: (9)

Does really nobody know what kind of reardiff is in the UK STI gearboxes?!?
Nobody who did a swap?
Please let me know!

FB Tuning

iTrader: (30)

Jap spec 6 speeder runs 3.9 front diff with 30:30 drop gears, and therefore a 3.9 rear diff

UK spec 6 speeder runs 3.9 front diff with 30:33 drop gears, and therefore a 3.5 rear diff

If you are transplanting a UK 6 speeder into a UK/euro classic with 3.5 R160 rear diff, then you won't need to do anything with the rear diff - It will be fine, as is.

If you are transplanting a Jap 6 speeder into a UK/euro classic with 3.5 R160 rear diff, then you will need to get a R160 39:10 crownwheel and pinion (from a UK/euro 2.0 sport) and have it swapped into your existing R160 diff, to end up with a 3.9 ratio rear diff.

R180 and R160 Crownwheel and pinions are not interchangeable

Hope that helps

Austrian Impreza

iTrader: (9)

That was the information needed!
Many thanks for this!

Would the axles of the STI V7/8 fit then with R180 diff in a classic.
Of course I would have to change hubs and maybe the brembos in the rear, but is there any other thing needed for the STI?
Are the axles as long as these from the WRX 99/00?

Please let me know!

Austrian Impreza

iTrader: (9)

Are the MY 97/98 and MY 99/00 diffs the same?!
Need advice please!

FB Tuning

iTrader: (30)

No - The rear driveshaft inner CV axles are different lengths on the MY97/98
On the MY99/00 the shafts are both the same.

Austrian Impreza

iTrader: (9)

So the difference are the axles, not the diff.
Could I use one of the 97/98 WRXs in my 99/00 car?

FB Tuning

iTrader: (30)

No, both the diff and the inner CV joints are different.

You could put the earlier diff and shafts into your 99/00 and it would work.

Austrian Impreza

iTrader: (9)

Many thanks for the information!!!

Austrian Impreza

iTrader: (9)

And now I got stuck with the swap, as I planned to use the axles of the STI V7/8 and the R180 diff in the MY00.
The outer hubs do not fit the axles of the STI V7.
Even tried to splint the WRX axles with the STI axles... no way.
So I would need outer hubs form an STI V7/8 or I have to trow away all the parts I actually have got from the V7 and use the WRX 3.54 diff in the rear!
One more idea is to use the pinion and crownwheel from a WRX R160 diff in the R180 diff, could this work?
So I would be able to use even the R180 in the rear and could keep the propshaft unshortened as well, no further extra costs, which rised extremly!
Many thanks for your help in advance!
Markus

911

Markus:
call David on Welcome to the API website he has a technician who does this kind of thing all day.

Very easy to approach and very knowledgable, AND he has all the parts too!
Graham

Austrian Impreza

iTrader: (9)

Graham, I know David of course and he is THE man who knows the hints!

Iīm only gonig a path nobody seems to do normally.

I want to keep the R180 diff without swapping the outer hubs and to brembos in the rear.
The axles of the STI are useless okay I can go with this, but is the STI V7 diff able to be used with the innerparts of the R160 3.54 diff out of a WRX?!?!?
Thatīs what I want to do!