A snaking, high-desert road course is the ideal test of the all-new 2018 Audi S4 and S5—cars that are spawned from the petri-dish of their ultra-high performance stablemates, the Audi R8 and RS. (To clarify: the German automaker’s nomenclature for sedans, coupes and roadsters begins with its volume-leading base “A” models, and then imbues them with sports-minded looks and more driving character and labels them “S.” The top-level fliers, penned with race-themed cues and hardware, are injected with lightning-quick mojo and the “R” moniker is applied.) We put the newest S4 sedan and S5 coupe models to the test across almost 200 miles on a collection of roadways that started in Palm Springs.

After updating its popular A4 sedan and A5 coupe models last year, Audi has now launched the Teutonic enthusiast S4 and S5 siblings for 2018. At first glance they may seem similar, but each S model features bespoke design differences, as well as specially tuned powertrains, and a collection of luxurious options that give the model its own level of prestige. The sedan seats five, while the coupe and cabriolet versions carry four.

On the outside, there’s sleek sheetmetal that has been redesigned with a few new dramatic shapes, creases and crisp wraparound lines that emphasize the vehicles’ length, while muscular wheel arches accentuate the sports-minded appeal of standard 18-inch (optional 19-inch) wheels. Up front, the S4 wears full LED headlights with LED daytime running lights, and a wider and flatter version of Audi’s single-frame grille with aluminum-optic double-blade bars. LED taillights, S-model-specific quad exhaust outlets, and a rear trunk lid spoiler punctuate the back. Notably, the S5 is both wider and lower with a number of updated elements; a more prominent power bulge on the hood is meant to emphasize its athletic prowess. Red brake calipers are available with the sport package and enhance its alluring style.

Inside both models is a three-spoke, flat-bottom and sport-designed multifunction steering wheel with shift paddles, plus a three-zone automatic climate-control system, and eight-way power front seats with four-way power lumbar adjustment for the driver. Lush, sporty seats feature contrast diamond stitching, pneumatic side bolsters, and a massage function. The S5 coupe adds a panoramic sunroof, ambient LED lighting (available with up to 30 color settings), and aluminum matte brushed or available Carbon Atlas trim inlays. Reinforcing Audi’s reputation for cutting-edge technology, both models offer a Virtual Cockpit with a 12.3-inch display, MMI Touch with handwriting recognition, and a full-color Head-up Display. The Virtual Cockpit in the S4 features a “sport” display mode that places the tachometer and speedometer to the front and center of the display and adds a boost gauge and lap timer.

Standard features in both models include a 7.0-inch color driver information display and a 7.0-inch TFT color center infotainment display; also included are Audi Smartphone Interface with Siri Eyes Free integration, Apple CarPlay, and Android Auto. Available Audi Connect mobile applications support remote services such as remote lock and unlock capability; online car finder; and curfew, speed, and valet alerts.

Both cars boast a 3.0-liter V-6 engine that swaggers with 354 hp and 369 lb-ft of torque. Along with an eight-speed Tiptronic automatic transmission that can be activated by steering-wheel paddle shifters, this combination asserts its power in a sprightly manner. These vehicles can reach 60mph in 4.4 seconds with a top speed of 155 mph. All models are equipped with standard Quattro all-wheel drive that is engineered with active torque distribution to both axles.

Audi’s newly developed front and rear aluminum suspension provides both a sporty driving experience and more comfort for long distances—like our drive through the Sonoran Desert. The redesigned, lightweight front (S4 and S5) and rear (S5) five-link suspension promises greater steering precision and handling. Other benefits of the new suspension system and updated electronics include standard Audi Drive Select with four different modes—comfort, auto, dynamic and individual—that adjust gear shift points, steering, throttle response, damper control and adaptive cruise control. An optional Sport Adaptive Damping Suspension with a new suspension control unit (S sport package) uses software and sensors for optimal suspension and damping control, while available Dynamic Steering offers a variable steering ratio that adjusts based on vehicle speed and the Audi Drive Select mode setting.

We drove both the S4 and S5 and, although the coupe sheds two doors it’s a tick more portly on the scales. It was our favored ride and felt lighter on its feet. While weaving through the desert, we felt safe and cosseted within the luxury-laden, high-tech interiors of both models as we cut through the environment with precise and predictable handling. Audi’s “Hot V” twin-scroll turbo cranks out power starting at 1,350 rpm and moved the new Ss with alacrity; somewhat heavily-weighted steering followed our point and intention in a delightful fashion, while the mechanicals and electronics provided behind-the-scenes guidance in a manner that brought assurance—and excitement.

The five-passenger S4 sedan and four-passenger S5 coupe are available in two trim levels. The S4 Premium Plus starts at $50,900 and the S5 Prestige begins at $54,600 (for those who enjoy top-down motoring, a cabriolet version of the S5 starts at $62,300). Destination fees add $975.

Images courtesy of Audi