An extra hundred horses thunder under the hood of the new Audi S4

Choosing a vehicle, especially a performance model, is not always a question of logic, but if it were, you’d be damn near obligated to pick the S4.

The 2018 Audi S4 represents the fifth generation of S-badged compact sport sedans in North America. Most notably, the S4 rides on the B9 generation A4’s lighter, longer platform and redesigned five-link front suspension. Building upon a more nimble chassis is a more potent engine. Replacing the previous generation’s supercharged V6 is a twin-scroll turbocharged V6 connected to an eight-speed automatic transmission. The 2018 S4 also features an available Quattro sport rear differential for more effective torque distribution.

Vehicle Introduction & Overview

By 1999, Americans were quite familiar with Audi’s A4 sport sedan. Introduced to North America in 1995, the A4 stood out among luxury sport sedans with its Quattro all-wheel drive system and Tiptronic automatic transmission. Quick and precise, the B5 generation A4 was an effective performance tool – but the U.S. longed for something hotter. In 1999, our prayers were answered; the S4 debuted with a twin-turbocharged V6 and more capable performance hardware.

An Audi performance model is like a diminutive, sweater-clad gentleman with a fifth-level black belt

Since then, the S4 has solidified its niche between traditional sport sedans and German muscle cars (i.e. BMW’s M3 and Mercedes-AMG’s C63). As the performance and price gap between these micro-segments has widened, competition has intensified. The new S4’s main rivals, BMW’s 340i xDrive and Mercedes-AMG’s C43 AMG, pull go-fast bits from their respective high-performance counterparts, but the S4 works from the other direction, enhancing the A4’s capabilities.

Though the S4 has never deviated from its mid-range performance path, it has wielded a number of different weapons along the way. The bi-turbo powertrain was replaced by a 4.2-liter V8 in 2003, and then a supercharged V6 in 2009. The latest and most efficient solution is a single, twin-scroll turbocharged V6 with more power than any preceding S4.

Trim Levels & Features

An Audi performance model is like a diminutive, sweater-clad gentleman with a fifth-level black belt. Identifying its ability is difficult, but underestimate it, and you’ll pay the price. The all-new S4 is most easily distinguished from the A4 by platinum treatments to its single frame grille, air intake slats, mirror covers, and rear diffuser. Other clues include unique 18-inch or optional 19-inch, five-spoke wheel designs, quad exhaust ports, and subtle S4 badges on the grille and trunk. These subtle accents compliment the A4’s hard edges, large grille, and brilliant exterior lighting for a sleek, mature aesthetic.

For a bit more visual flair, the available S Sport package ($2,500) includes red brake calipers front and rear, plus a sport adaptive suspension system and sport rear differential (evidently Audi can’t resist stamping the word “sport” on everything to emphasize how exciting you are). The final performance option is Audi’s variable-ratio steering system — a $1,150 box to check.

The standard Premium Plus S4 ($50,900) is nicely equipped with LED daytime running lights, LED taillights, heated S sport bucket seats, three-zone climate control (with rear controls), auto-dimming, power-folding, and heated side mirrors, a Bang & Olufsen sound system, a backup camera, and Audi pre sense basic safety technologies.

Upgrading to the Prestige ($55,800) trim introduces Audi’s 12.3-inch Virtual Cockpit full digital driver display, an 8.3-inch center infotainment display, navigation, a head-up display, rear cross-traffic assist, and vehicle exit assist. Each of these features (apart from the head-up display) can be added to the Premium Plus model via the available Technology Package ($3,100).

Technology Overview

Audi continues to hold an edge when it comes to segment-leading technology, with advanced safety and convenience features offered in more accessible models.

Audi didn’t give the S4 a cursory glance; it toiled over the details to scale the A4’s performance dramatically.

Though we’d love to see Audi’s stunning Virtual Cockpit on the list of standard equipment in the S4, it’s worth every penny to upgrade from analog gauges. The reconfigurable display ports navigation, media, and telemetry information from the center display to keep your eyes forward (and give you a visual thrill). While Virtual Cockpit is available in the A4, S4 models feature a unique configuration that centers the tachometer.

Other standard tech highlights include two front USB ports (and none for backseat riders), Apple CarPlay and Android Auto, Sirius XM, HD radio, voice command functions, Bluetooth audio streaming, and a Bang & Olufsen 19-speaker 3D sound system. Audi loads the S4 with plenty of gadgets, but what truly sets the car apart from its rivals is feature usability. From song selection to route guidance, Audi’s MMI system is an intuitive delight.

Interior Fit & Finish

Inside, the S4 is everything we love about the A4, plus some wicked good front bucket seats, Alcantara treatments, and contrast stitching. Leather and brushed metal surfaces line every common touch point, while high quality materials fill in the gaps. Specific to the S4 and S5 are Alcantara inserts for the door panels and seats which give the cabin a — sorry I have to — “sporty” feel.

Thanks to the new A4’s longer wheelbase, the S4 has ample room for four large adults, or a tighter fit with five passengers. Six-footers can sit front-to-back with leg and headroom to spare, and split-folding rear seats expand the S4’s utility beyond a generous 13 cubic feet of trunk volume. Physical space is great, but the impression of space is equally important. In this regard, the S4’s wrap-around dash and connected horizontal air vents put all riders at ease.

Driving Performance & MPG

Here’s the deal: out of the box, a standard A4 (and even more so one equipped with the sport package) is so composed, Audi could have just bolted in its turbocharged V6 and called it a day. The A4’s platform is balanced, its adaptive suspension is intelligent, and its steering is responsive. But Audi didn’t give the S4 a cursory glance; it toiled over the details to scale the A4’s performance dramatically.

Miles Branman/Digital Trends

Let’s start with the engine. While the A4 makes do with a robust 252 horsepower, the S4 adds 40 percent more grunt, meaning 354hp and 369 pound-feet of torque are channeled to all four wheels via an eight-speed automatic. Some may miss Audi’s dual-clutch S-tronic seven-speed gearbox, but the eight-speed is just as quick, and is better suited to this engine. Lower gears are shorter for quicker acceleration, and taller gears are longer for better fuel economy (21 city/31 hwy mpg).

Instead of using a twin-turbocharged mill, Audi placed its single turbo within the V of the engine, shortening the distance forced air must travel to each cylinder bank. As a result, the S4 develops peak torque from 1,370 rpm to 4,500 rpm and max horsepower from 5,400 to 6,400. This gives the S4 real firepower from just about anywhere in the rev range; in our experience, there’s a good surge from 1,500 rpm onwards.

The S4 generates a good surge of fire power from just about anywhere in the rev range.

A base-spec S4 benefits from six-piston front brakes, four-piston rear, a re-tuned suspension system with Audi Drive Select’s four driving modes, and a sharper fixed ratio steering system. In its no-option form, the S4 is a rush, but the optional Quattro sport differential and dynamic steering system raise the bar significantly. Audi’s standard center differential can move up to 100 percent of available power between the front and rear axles, but the sport differential can load every bit of torque to a single wheel.

With this option, the S4 applies power more intelligently and carries greater speed out of corners. Fixed or variable ratio steering will depend on driver preference (which is why Audi makes the system a standalone option), but we prefer the feedback and responsiveness of the dynamic steering unit.

Audi’s S4 is precisely what we hoped it would be: an A4 stacked with lean muscle.

Safety

In addition to electronic stability control, ABS, dual-stage airbags, side airbags, knee airbags, and head curtain airbags, every S4 comes with Audi pre sense Basic and City. Pre sense Basic pre-loads the brakes and raises windows when a potential accident is detected, while pre sense City can apply brakes at up to 52 mph if the driver fails to respond to a potential collision with a vehicle or pedestrian.

Conclusion

We’re quite taken with Audi’s all-new S4, but, frankly, we expected this outcome. Audi’s game plan is simple, but effective: hone the A4’s handling, layer on more than 100 extra horses, and spice up its exterior. As a result, the S4 is quicker than its BMW and Mercedes-AMG rivals at a price smack dab between the two. Choosing a vehicle, especially a performance model, is not always a question of logic, but if it were, you’d be damn near obligated to pick the S4.

2018 Audi S4 First Drive