Vindictively quick on patchy UK tarmac. In fact, stretching this car to anything like its potential is an exploit of mind over matter. You must override the monkey-brain that screams lift and allow the car simply to get on with it.
The truth is that 444bhp is rather less than Audi Sport – née Quattro GmbH – is accustomed to dealing with. An RS7 Performance makes near enough 600bhp and its lengthy chassis needs to corral an additional 200kg on top of the RS4’s 1715kg. The new car is within Audi’s comfort zone and it shows because, on any kind of road you care to fire it down, the stability the chassis demonstrates is staggering.
As well you might expect in a vehicle touting the latest quattro driveline and 265-section tyres all-round (Continental SportContact 6s, in the case of our test car). Geared for RennSport duties, in this case the set-up uses an eight-speed torque-converter – effortlessly smooth and well suited to this application – that sends 40% of torque to the front axle in normal driving. With the loss of traction, up to 85% goes to the front, or 70% to the rear, and its activities are just about detectable.
The passive set-up of our test car feels like it's tuned for sweeping A-roads. Wheel articulation is succinctly controlled and body roll limited to what you’d expect to find in a pretty focused hot hatch. Direction changes are absolute, though the process is never quite as invigorating as it is in the Alfa Romeo Giulia Quadrifoglio, with its quicker ratio and thin-rimmed wheel. Far more of a cruiser, the RS4 Avant is nevertheless the quicker machine on the sort of roads we’re familiar with.
That stability means the steering – light, precise, but dead in your hands – along with the throttle and brakes can be used with impunity in almost any combination. Flat-out acceleration in second and third through an undulating ess-bend? Dispatched with contempt. Heavy braking on the way into a low-speed corner on a shabby surface? The RS4 is planted. What you have to ask yourself is whether this is what you really want in a performance car. And for a family estate, it might well be.
The three-stage stability control system is particularly nicely calibrated, secretively trimming drive here and there and, as alluded to, working with the torque vectoring to help the RS4 corner – sorry – as if it were on rails. But what if you wind it off? Set the electronic rear sport differential to Dynamic and the RS4 can indeed entertain, its tail end tentatively creeping out during medium-speed bends. It’s not a natural like the Mercedes-AMG C63 Estate, though, and defaults to understeer more often than not. As for the power oversteer in which the Mercedes seems to delight, good luck with that – you’ll need a hefty weight transition to begin the process.
Weight is also a pivotal factor in ensuring the primary ride is fluid, and settled, which is exactly what you want in a practical car you might very well use for a day-long excursion. Issues can arise at lower speeds, where the stiffness required for that economy of movement when you’re pushing on translates into a pronounced fidget. For a car of the RS4’s ability, it's perfectly acceptable – but if you’re expecting Audi to have worked miracles, you may be disappointed.
We did have a brief go in a car fitted with RS Sport suspension plus with Dynamic Ride Control, however. It costs £2000 – not a lot, for a major option in the context of a £60,000 car – and hydraulically links three-stage adaptive dampers diagonally across the car. The idea is that they conjointly diminish pitch and roll during braking, acceleration and cornering. The most tangible benefit is that you can set the damper rate to Comfort, which goes a long way to mitigating that low-speed jostle and gives you a convenient amount of body roll through corners.