steved

There has been some talk on this forum about upgrading the current S4's brakes to the larger units of the RS4. I spoke with Guido Frensemeyer of Mov'it in Germany about this car. His comments are as follows:

The RS4 was created for Audi to use up some of the A4 Avant bodies they had left over until the new A4 is announced next year. This limited edition model is expensive in Germany, retailing for around 140,000DM.

The RS4 comes with 2 piston floating calipers (heavy Lucas or ATE units) and a 2pc disk with aluminum center hat, similar to the BMW M5 in Europe. This disk is rather large at 365x30mm and requires 18" rims. The RS4 knuckle assemblies are aluminum and much thicker than the cast iron knuckles on the S4's. As a result, the caliper offset is such that the RS4 calipers will not bolt on the S4's cast iron knuckles.

The RS4 brakes are effective when new but deteriorate quickly with mileage (kilometers). They are still much more effective than the stock S4 brakes.

If you want to upgrade to RS4 brakes, you'd better consider changing the knuckles as well and upgrading to 18' rims. With 18" rims and the price of the Audi Rs4 parts (they won't come cheap), you could upgrade to a 15"/380mm brake kit with 4piston calipers for much better cooling and braking. Mov'it has already sold three 380mm kits to German RS4 owners. SD<p>Steve D'Gerolamo

Chris T

Thanks Steve. Mark that one off the list!

RS4.org - DaveH

The RS4 is a continuation of the RS2 and is designed to be the final tribute to the current A4 before its replacement next year. Audi are also planning RS cars for then end of other models A8 next then A6. 70% of all S4's in Europe are Avants, the S4 saloon is due for deletion at the end of this year with the Avant mid next year. The only Avant only body panel the RS4 uses is the roof so Audi must have 3900 Avant roofs lying around, the bonnet is common to both S4 models, there remainder of the body panels are unique to the RS4. THe RS4 is produced in 2 factorys, Ingelstat and Nerkesaulm (spellings ?) where as the A4/S4 is produced only at Ingelstat.

The actual rotor has minimal contact with the "center hub" to reduce heat transfer

The RS4 has modified air ducting to assit brake cooling

Audi's web site quote DM 130,000

It certainly would be cheaper to fit a third party solution

LCP

Dave, what light can you shed on the modified air ducting?

RS4.org - DaveH

Its hard to see but there are diffinate changes, i will pic one up on a ramp soon