RS2 Rear Brakes on Coupe

[The Spanish]

As it says, starting a project to fit RS2 rear brakes on Coupe.

First and most important a big thank you to Roger (Audi_CQ)

Coupe rear suspension setup is different from RS2 one, wheel bearing are different diameter, wheel housings and hubs have diffrente geometry so some changes have to be made.

The most important change goes into the real wheel housing. It needs to accomodate the larger rear wheel bearing, the Porsche parking brake (drums inside the disk) the RS2 wheel hubs, the RS2 rear caliper Carrier an then calipers, brake disks and alloys.

From the original RS2 rear wheel housings there was some machine work done to bring the inside diameter and outside diameter (by adding a ring of metal) to the exact same values of the RS2 one. Also holes to mount the RS2 caliper carriers where done and the Carrier need it to be modified to adjust the caliper into the S2 position (in front of the rear suspension)

Here are some pics of the Coupe rear housings with all the modifications + powdercoating.

1st

[The Spanish]

Another

[The Spanish]

And another with the carrier

[The Spanish]

From the back

[The Spanish]

Next step will be the drivesafts (soon)

At the moment I got from tots (www.totsteile.ch) two rear drivesafts from the RS2. I know one of them is the exact same length as the Coupe so just needs to be bolted. The other one is different so I am planning on 3 options:
1. Swap the outerjoint from the RS2 drivesaft to the Coupe drivesaft (both are the same width but I am not sure is possible)
2. Find in the audi family something usefull. Roger pointed me out that the UR front drivesafts are the same lenght as the Rear I need so could be a possible job.
3. Cut the other RS2 drivesaft to the correct measure (Roger did this and it is working brilliant in his car (two years with 400+ bhp) Mistake (this option is only good for 150 bhp max.
Next is very straightforward, just fit the RS2 rear wheel hubs, parking brake, caliper carrier, caliper, brake disk and wheel.

Will post when I have updates

[Jeffer]

Hi Rafael,

That looks great mate. Excellent work done on that hub.
I'm going for option one, I did measure the the splines of the RS2 and the S2 driveshaft where the cv joint connects to, and these ar the same diameter. So that should work.

Cheers

[The Spanish]

Hi Rafael,

That looks great mate. Excellent work done on that hub.
I'm going for option one, I did measure the the splines of the RS2 and the S2 driveshaft where the cv joint connects to, and these ar the same diameter. So that should work.

Cheers

If Option 1 works everything left to do is just unbolt and bolt stuff on the car

[ADU_S2]

Its hard work doing all this will look great when its finished. I have the complete rs2 setup on my coupe, was done years ago by a friend of mine had to have some of the parts machined etc but definetly worth doing.

[audiman]

good work, its good to see some serious engineering going on. It there much difference between s2 vs RS2 wheel bearing dia.??? is there enough metal in the hub to machine out?

[Audi_CQ]

Next step will be the drivesafts (soon)

At the moment I got from tots (www.totsteile.ch) two rear drivesafts from the RS2. I know one of them is the exact same length as the Coupe so just needs to be bolted. The other one is different so I am planning on 3 options:
1. Swap the outerjoint from the RS2 drivesaft to the Coupe drivesaft (both are the same width but I am not sure is possible)
2. Find in the audi family something usefull. Roger pointed me out that the UR front drivesafts are the same lenght as the Rear I need so could be a possible job.
3. Cut the other RS2 drivesaft to the correct measure (Roger did this and it is working brilliant in his car (two years with 400+ bhp)

Next is very straightforward, just fit the RS2 rear wheel hubs, parking brake, caliper carrier, caliper, brake disk and wheel.

Will post when I have updates

A few small comments:

1. On the driveshafts I had to measure from, this swap wasn't possible, but not sure if it was a genuine S2 shaft.

2. All UR-Q driveshafts are the same lenght so both front and back shafts can be used, but outer joint has to be changed. I used a 200 20v front CV

3. Not quite right. Worked with org. 136hp engine on track and strip, but the new engine and hard clutch killed the cut&shut driveshaft very quickly. Swaped it for the UR-Q with 200 20v outer joint.

A pic after powdercoating :

[Audi_CQ]

Another one :

[Audi_CQ]

good work, its good to see some serious engineering going on. It there much difference between s2 vs RS2 wheel bearing dia.??? is there enough metal in the hub to machine out?

S2=75mm , RS2=82mm

After maching out to 82mm you have to machine the outside and press on a ring to add strenght. Without this ring the carrier wouldn't be to thin.

Cheers,
Roger

[The Spanish]

Jeffer is trying out the S2 drivesaft conversion.

I will try it in around 3 weeks on my car also if he has not done it yet.

Meanwhile if anybody has a UR Q drivesaft lying around PM me

Cheers,

[Tommy200rs]

More cost efficient way is to do it the S8 way. Not so good braking power like with rs2 rear calipers but far more efficient than stock rear brakes in S2 COUPE. This is not valid for S2 sedan. Sedan and avant are a another story with different caliper from A4 S4 bt.

NEEDED:
- S8 rear caliper carriers 2x
- Ur V8 calipers or AAN modified for 2mm bigger dics 20mm->22mm
- small shims to have the disc centered between carrier
- Audi A3 disc 280x22mm with changed bolt pattern and larger hub hole (easy with cnc)

[The Spanish]

More cost efficient way is to do it the S8 way. Not so good braking power like with rs2 rear calipers but far more efficient than stock rear brakes in S2 COUPE. This is not valid for S2 sedan. Sedan and avant are a another story with different caliper from A4 S4 bt.

NEEDED:
- S8 rear caliper carriers 2x
- Ur V8 calipers or AAN modified for 2mm bigger dics 20mm->22mm
- small shims to have the disc centered between carrier
- Audi A3 disc 280x22mm with changed bolt pattern and larger hub hole (easy with cnc)

I know but I am using 5x130mm Porsche hubs, rotors, and wheels at the front. And because I don't want to use different wheels at the front than at the rear I need a solution with 5x130mm Porsche hub.

At the moment I have some adapters from 5x122mm PCD to 5x130mm PCD which I don't like but makes the car running.

Plus I want it to say Porsche in red on the four corners