I just recently got a 2007 RS4 and took it out autocrossing the other day. It's classed as BS, hard to believe for such a heavy car, but OK. It really took me by surprise, I tried with traction control off and in Sport mode but the car was a real beast compared to cars I've run in the past, a lotta fun though. I haven't done a thing to the car other than pump up the tires to 41 all around, run-flat street tires and all.

By my second run I noticed a lot of understeer and it really pushes with all that weight. I also noticed something biting, like the traction control wasn't off, I heard a clicking when I cornered hard and could feel the brakes kicking in (sometimes I feel this just around town ). There was really a fine line where I could get the car to maneuver and I'm still getting used to it. We tried playing with tire pressures a bit but if it was an improvement it wasn't much (we tried lower in the front, higher in the rear by 2psi).

So two questions then, if this is traction control is there no way to turn it completely off? Am I better off just leaving it on? What would improve the understeer.

 

Did you turn BOTH levels of traction control off? If you just hit the button once, that disables one level (ESP I believe), if you push a second time and hold for a few seconds, it takes everything off (ESP and ASR.)
The second level of electronics only comes on in really extreme situations as you described above.
Careful though, as this car with everything off can be easy to lose control of.

 

I believe there is a recall or TSB on the RS4's hydraulic suspension, so check into it. Being all wheel drive and nose heavy, the car is going to naturally understeer no matter what. Many RS4 owners get the Ohlins Motorsport suspension to improve handling.

 

Thanks Guys, I will try the second setting and see what happens and I will be careful, I don't mess with any of this on the street though.

No plans at this time to do anything with the suspension, just play with tire pressures a bit. I do need new tires at some point next month which may help bite a little more. I'm thinking of trying a street tire class next time, like STX or something.

 

Suspension is one thing but far more important:
have u ever heard of the Haldex Kits?

a friend of mine uses the MTM one in his new TT-RS which also uses the Haldex-Quattro. After the installation u have 3 modes: eco, sport and race. In race mode the power is constantly delivered 50:50 and he told me that it is like day and night. the car tends much more to oversteer and it feels much lighter through the corners, he is never using the other 2 modes, the race mode makes it a real quattro and a different animal!
i don`t know if there is an MTM distributor in the US but it is totally worth the money.

http://www.mtm-online.de/en/products/mtm-drive-technology


Sportec, a well known Porsche tuner from switzerland, is also offering some Haldex kits:

http://www.sportec.ch/page7743.html


u may have to contact those tuners what to use in your RS4.

cheers

 

I believe the MTM Haldex unit works only with Haldex-controlled AWD systems-which isn't used in the B7 RS4, it's only in the A3, S3 and TT/TTS/TTRS. The B7 RS4 uses the Generation V Torsen T3-here is mine with MTM's supercharger kit, sitting on Stasis Ohlins:

 

you are right, i thought Audi did use a Haldex derivate in the QB6 as well.
so a good suspension kit + maybe a pair of stabis should do the trick.

nice car btw, RS + MTM is a great combo.