The S4 has always occupied a pleasing middle ground in Audi's lineup. With a bigger helping of power, better handling and a bit more style than a standard A4, the S4 is a lovely car that's nowhere near too stiff or unmanageable for daily driving duties. The 2018 S4, thankfully, carries on this tradition of being a beautifully sorted, yet highly capable sport sedan.

New boost

The 2018 Audi S4 has a 3.0-liter V6 engine under its hood, but unlike its predecessor, the new mill is turbocharged instead of supercharged. This results in 354 horsepower and 369 pound-feet of torque -- increases of 21 horsepower and, more importantly, 44 pound-feet over the supercharged engine. Together with the ZF-sourced eight-speed automatic transmission, Audi says 60 mph will arrive in just 4.4 seconds, though the engine is still efficient enough to receive respectable EPA-estimated fuel economy ratings of 21 mpg city and 30 mpg highway.

When pedaling it hard in Dynamic mode, the drivetrain is fantastic, with no turbo lag to speak of. Right-now thrust is available all the time, with peak torque online from 1,370 to 4,500 rpm, allowing for wicked shots away from stoplights and out of corners. In its full automatic mode, the transmission's gear changes are quick and well-timed, but a manual mode is also here for those looking for a more involving drive experience. The only downside to selecting your own gears is that plastic steering wheel paddles truly feel cheap.

If you're hoping for a manual transmission, well, I have bad news. The six-speed stick that was available in older S4s goes away for 2018. The automatic is now the sole gearbox option. Complain all you want, but the take rate for three-pedal S4s wasn't enough for Audi to warrant building them. I know, bummer. But the eight-speed auto is just fine.

Sharper dynamics

The new S4 is better suited to handling this increase of power, its Quattro all-wheel drive system using a rear-biased, 40/60 default torque split. The center differential can alter front-to-rear bias according to driving style and traction conditions, with up to 85 percent of the available torque going rearward. Raising the handling IQ of my test car further is an optional S Sport Package that adds a torque vectoring rear differential and adaptive dampers that all work together to make the S4 feel incredibly light on its feet. That's despite a hefty 3,858-pound curb weight, too.

Turn-in response is nearly immediate, with gobs of grip available on the S4's 245/40R18 Hankook Ventus S1 Evo2 tires. The brakes are muscular and understeer is never an issue, the rear end quickly rotating during spirited driving.

Enabling the Drive Select's Comfort mode simmers down the chassis and drivetrain. The steering gets lighter, the suspension relaxes, the transmission shifts at a more leisurely pace. For commuting or long highway sprints, it turns the sporty S4 into a docile machine.

As for knocks, I'll say the S4's steering is still numb on center like many Audis, and overall, the car might be a little too buttoned-up for its own good. It's incredibly fun, mind you, but could stand to loosen its collar a little. More growl from the exhaust would be a welcome enhancement.

Understated looks

Visually separating the S4 from regular A4s are slightly more aggressive front and rear fascias, aluminum exterior trim, a rear spoiler, quad exhaust tips and 18-inch, split-spoke wheels. These aren't huge tweaks, mind you, but I like the lower-key, under-the-radar style of Audi's S models. Compared to an M Sport-ified BMW, this one appears to be a sleeper.

Highlighting the cabin are leather sport seats with diamond-stitched Alcantara inserts that tightly grab onto passengers, with support in all the right places and, interestingly, have a standard massage function up front. A flat-bottom steering wheel and brushed aluminum trim complete the additions to the quality interior, the rest of which is comprised of high-quality plastics and lots of soft-touch surfaces.

Strong tech

Quarterbacking infotainment functions in the S4 is Audi's intuitive and responsive MMI system with an 8.3-inch center screen, navigation, Wi-Fi hotspot and Bluetooth. Spitting out the tunes is a crisp-sounding Bang & Olufsen audio system with 19 speakers sprinkled throughout the cabin. MMI also supports both Apple CarPlay and Android Auto for those who prefer to hand infotainment controls to their phones. For juice, there are two USB ports in the center armrest, a 12-volt outlet on the lower center stack and one on the back of the center console for people in the rear.

Enlarge Image

The 12.3-inch Virtual Cockpit dash is also available on the S4, with a new Sport view that places a large tachometer front and center, flanked by the Google Earth map and other infotainment information.

For safety, my tester comes equipped with forward collision warning with automatic emergency braking, blind-spot monitoring, backup camera and rear cross-traffic alert, which is always handy when backing out in busy parking lots. Adaptive cruise control and lane-keep assist are also available.

How I'd spec it

When it comes to building my ideal S4, making it the most entertaining daily driver possible is my main goal. With that in mind I would begin with the $52,375 base car, which includes $975 destination. From there I'd add the $2,500 S Sport Package for the adaptive dampers and torque vectoring rear differential to blaze back roads, be better equipped for occasional open track days and have the option of nice ride comfort. I also really like the Virtual Cockpit that is part of the $2,600 Navigation Package and will also spring for the $575 Navarra Blue paint job. That brings the price tag of my S4 to $58,050. The car pictured here, with S Sport Package, Navigation Package and Dynamic steering system costs $59,550.

Enlarge Image

Head of the class

With cars like the BMW 340i xDrive, Jaguar XE S AWD and Mercedes-AMG C 43 sedan all starting in the low-to-mid $50,000 range, the S4's competition is rather fierce. The 380-horsepower Jaguar and 362-horsepower Mercedes have a little more power than the Audi. But the S4 can claim acceleration bragging rights with its 4.4-second 0-to-60 mph time -- it's quicker than all the rest.

Really, the only standout feature from the competitive set is that the BMW can be had with a manual transmission. But if you're like the majority of buyers, who don't absolutely need a stick, the S4 is arguably the best bet in the class. Peppy power, impressive handling, good ride comfort, handsome looks and trick interior tech make it the most complete and compelling car of the bunch.