The Audi A4 sedan is a very good car. It's got some of the best dashboard tech in the business, quite good turbocharged and all-wheel driven performance and an aesthetic that successfully pulls off "understated design" without looking boring. As I said, it's a very good car... perhaps one of the best in its class.
The new 2018 Audi S4 takes this "very good car" base and transforms it into a "fantastic driver's car," turning up the wick on the power, handling and its pilot's pulse. Yet even this sharpened-up sport sedan retains the core of understatement that is at the core of the A4's design and character.
The new S4 makes 354 horsepower and 369 pound-feet of torque thanks to its 3.0-liter, turbocharged V6 engine. Audi has tucked its twin-scroll turbocharger right between the V6's two cylinder banks in what's called a "hot inside V" configuration. Of course, the Audi isn't the first to do this, but tells us that it chose the setup because the shorter exhaust paths help improve the turbo's responsiveness to throttle inputs. And responsive it is, making its peak torque at a very low 1,370 RPM.
The new engine is also 31 pounds lighter than the previous-generation S4's supercharged unit.
The new 3.0T V6 is mated to an eight-speed torque-converter automatic transmission. Paddle shifters are standard, but I'm a bit disappointed by the hollow plastic feel of the paddle, especially considering the S4's price. I'm even more disappointed that the S4 no longer offers a manual gearbox in any configuration. Audi says that the vast majority of buyers who actually shell out for S4s opt for the auto-boxes, so... I guess this is your fault.
I'm not at all disappointed by the performance. In a straight line, the sedan launches with a surge of power, even without activating the hidden launch control mode. The S4 boasts a 0-60 mph time of just in 4.4 seconds, which Audi claims is faster than the Mercedes-Benz C 43 and the BMW 440i. The S4's engine and gearbox have amazing synergy. The shifts are smooth -- almost imperceptible in the most comfortable settings -- and the combo always seems to be in just the right gear, thanks in part to the generous and flat torque curve.
You know what they say about power without control -- the former means nothing without the latter -- so Audi has put a solid effort into making sure that the rest of the S4 has the traction, handling and stopping power to make best use of its 354-horsepower engine.
After leaving the gearbox, torque is split between all four wheels via the standard quattro all-wheel drive system. Quattro, for the S models like the S4, is more performance oriented with a sportier, rear-biased 40/60 default split. The center differential can alter that front-to-rear torque split dynamically depending on the moment's needs, and an optional sport rear differential adds even more flexibility by enabling torque vectoring across the rear axle for better traction and control when cornering.
Helping to keep the wheels planted is a five-link multilink suspension at all four corners. Available active dampers continuously adjust in response to road conditions, drive select mode and cornering demands to balance a firm, responsive ride with the ability to soak up bumps.
The S4 features four Drive Select modes -- Eco, Comfort, Dynamic and Individual -- that adjust the characteristics of the handling, throttle response and overall performance. The S4 even has a button right on the steering wheel that can be remapped to toggle between the Drive Select modes without taking a hand from the wheel, which is great for when you stumble upon a sweet stretch of road and need to quickly hop into the Dynamic setting for a few curves. (However, on examples that have the optional "cold weather" package installed, that remappable button is replaced with a toggle for the steering wheel heater.)
Overall, the S4's handling feels much more neutral than the current A4 or even the previous S4 model. There's much less noticeable understeer -- which has plagued previous quattro vehicles -- but also the sedan is nigh impossible to oversteer, even with its rear-biased power split and sport differential. Steering was predictable and direct when chucking the S4 with zeal into a corner on public roads. It just goes where you point it without drama.
Even giving the throttle an exploratory squeeze mid-corner didn't upset S4. Rather than understeering out or oversteering into the corner, the sedan just plants and goes faster. There's definitely limit to how hamfisted you can be with the grip before understeer steps in, but I think reaching that limit would be tough outside of a racetrack.
I just wish the S4 sounded better. In the loudest Dynamic mode, the S4's exhaust note is still extremely subdued from the cabin. The Mercedes-Benz E400 Coupe, for example, had much more bark and burble and a much nicer sound. Then again, for fans of the S4's understated appeal, not attracting the wrong sort of attention with each upshift may be seen as a selling point.
The dashboard tech on the new Audi S4 is nearly identical to that of the A4, which means it's quite good -- the best in the business, if you ask me, with its Nvidia-powered hardware and smartly designed Audi Connect software and Virtual Cockpit.
The S model has at least one unique tech trick: a new Sport view for the Virtual Cockpit instrument cluster that enlarges the tachometer, placing the digital gauge at the center of the display. In this mode, the driver can still view the Google Earth map and other infotainment functions in positions, flanking the prominent tach. Of course, the standard Virtual Cockpit display modes are also still available and just a tap of a steering wheel button away.
Audi's complete suite of driver aid tech is also available, including adaptive cruise control with traffic jam assist, a surprisingly subtle lane keeping assisted steering system, blind-spot monitoring with rear cross-traffic alert, and a front collision mitigating auto-braking system that can even look across lanes, braking to prevent accidents when turning left across traffic.
The S4 starts at the Premium Plus trim level, so it's fairly well-equipped out of the gate. However, Audi has made some interesting amenity choices for this performance models. For example, massage seats are a standard feature. Making heavy, active seats a standard feature on a high-performance sport sedan -- where every pound of extra weight makes a difference -- seems like an odd choice by Audi. Of course, I'm not going to complain too hard about having my backside caressed, and the seats' adjustable bolsters and Alcantara inserts are quite grippy.
The S4 gets an EPA estimated rating of 21 mpg city, 30 mpg highway and 24 mpg combined, which isn't great but not too bad for a sport sedan. However, I didn't crest an 18 mpg average during my day of testing, even during the most relaxed segments of the trip.
The 2018 Audi S4 starts at $50,900 for the Premium Plus entry point or $55,800 for the better equipped Prestige model before a $975 destination charge and any option boxes you happen to check.
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