The Audi RS4 that I detailed in Part II is in its own category. Of the three strictly S-version cars, I like the S6 ($72,000 base, $78,320 as equipped) the most. First, it has the version of Quattro all-wheel drive that’s used in the RS4 but not in the regular A6 with Quattro. By sending 60 percent of the power to the rear wheels, the S6 offers more balanced handling, as I elaborated on in Part II. The S cars are clearly moving in this direction; only the S4 still has a 50/50 split between the front and rear wheels. Overall, it seems that all the so-so characteristics of the other S cars are markedly better here in the S6.
Most important is accelerator response; the car always responds relatively quickly. Not so the S8 — and the 4 series cars could and should be better. One of the great underreported stories in automotive journalism: The popularization of by-wire (electronically actuated) throttles has introduced a response lag in many cars. At times it’s atrocious, and combining it with an automatic transmission often makes it worse.