Has anyone got any experience with swapping an S4 gearbox into an S3?
I am fitting an S4 13B 6 port into my S3, I would like to use the S4 gearbox as the original 12A box is noisey/worn and the S4 has much lower mileage. From what I understand changing the tail housing is fairly straight forward, but I am concerned that it will end up over geared as the diff is 4.1 in an S4 but 3.9 in my S3. Also which speedo drives should I use?
S4 gearbox in S3
Re: S4 gearbox in S3
use the S3 speedo driven gear and drive gear in the S4 box
1986 Series 3 13B Turbo II
http://rx7fb.com/viewtopic.php?f=2&t=2400
1992 Peugeot 205 1.9 GTI
1975 Honda SL125 Street Scrambler
http://rx7fb.com/viewtopic.php?f=2&t=2400
1992 Peugeot 205 1.9 GTI
1975 Honda SL125 Street Scrambler
Re: S4 gearbox in S3
I have a S4 box in my red RX2. It works fine with my 3.9 LSD. The gearing is better in the S4 box.
It's about 10mm longer than a S3 box iirc.
It's about 10mm longer than a S3 box iirc.
Back in sunny France
Re: S4 gearbox in S3
Thanks for the response guys. I will be using smaller tyres than the FC used, so hopefully this will negate the effects of the 3.9 final drive. I will be using the FB tail housing to account for the shifter being further back. What size tyres did you have TOOL?
Re: S4 gearbox in S3
Ah same as me then 
