2018 Audi S5 Cabriolet

Audi has set the performance bar high with the new-generation A5, even with its base turbocharged 2.0-liter inline-four engine. The A5’s chassis is tied down, braking is strong, and the engine and transmission work together like Shaq and Penny in their prime. It’s a complete package that puts pressure on its more athletic turbo V-6–powered sibling, the new S5, tested here in cabriolet form. The $63,275 starting price of the S5 convertible is $12,700 higher than that of the normal A5 cabrio, a significant chunk of change that raises expectations.

New with a View

This all-new S5 resembles its predecessor so closely that it looks more like a refresh than a full redesign, but Audi says the sheetmetal is completely different. If the previous-generation car ate nothing but cottage cheese and ran five miles a day for a month, like a boxer trying to make weight, it’d come out looking like this 2018 model. The more aggressive body sports wider wheel arches, a more sharply cut front end, and crisper edges where there used to be soft curves. The grille is flatter, and the headlights and taillights look sleeker and angrier. The result maintains the same general shape but presents a more hunkered-down appearance.

Visual distinctions between the S5 and the A5 are even less obvious. The metal trim around the lower air intakes pops more prominently, dual exhaust tips on each side replace the base car’s single units, the rear gains a diffuser, the grille slats are slightly tweaked, the mirror caps are metallic rather than body color, and the wheel designs are more distinctive. The most significant difference, of course, is the engine and transmission.

Power Delivery

As with the new S5 coupe and four-door S5 Sportback, the convertible has a new engine. Whereas the original S5 had a naturally aspirated V-8 and the facelift of that model employed a supercharged V-6, the new S5 boasts a turbocharged 3.0-liter V-6. The design incorporates a twin-scroll turbocharger tucked into the valley between cylinder banks, and under light loads, it can operate on the more efficient Miller combustion cycle.

This turbo V-6 makes 354 horsepower and 369 lb-ft of torque, increases of 21 horses and 44 lb-ft over the former supercharged six. And while the A5 now uses a seven-speed dual-clutch automatic transmission and offers the option of a six-speed manual (but just in the coupe), the S5 comes only with an eight-speed automatic. All-wheel drive is standard, and there’s an optional torque-vectoring rear differential that’s exclusive to the S5.

The S5 cabriolet outmuscles the A5 by 102 horsepower and 96 lb-ft of torque, but our test numbers don’t reflect nearly that big of a discrepancy. The S5 sprinted from zero to 60 in 4.8 seconds and ran the quarter-mile in 13.5 seconds at 103 mph, as compared with the 5.6 and 14.2 seconds at 98 mph we measured for the turbo-four-powered A5 cabrio with the seven-speed.

The A5 outperformed this more expensive model on the skidpad with grip of 0.96 g versus the S5’s 0.94 g. The S5 needed 158 feet to stop from 70 mph whereas the A5 did it in 145 feet. It’s a not a direct comparison, though, since this car was wearing Continental ContiSportContact 5P tires where the A5 was shod with Hankook Ventus S1 Evo 2, but both are summer performance tires on 19-inch wheels.

The S5 cabriolet puts up those performance numbers without the car ever feeling disturbed. The steering is quick and progressively gets heavier as speed increases, though it is all but completely numb. The chassis, which Audi claims is 40 percent more rigid than the previous model’s, is imperturbable even as it nears its limits. But the ride quality is stiffer than that of the A5 by a wider margin than the small performance difference would justify. Overall, though, the S5 is surprisingly good at playing the parts of both a suave, comfortable convertible for everyday driving and a dialed-in, focused machine to challenge your favorite roads.

Cabin Fervor

Audi has improved the functionality of the convertible top with the new model. On the previous generation, the car had to be parked and the driver had to hold a button until the top was completely up or down. Now the top can be opened or closed with a single touch of a button while driving at speeds of up to 31 mph. We measured its operation at 18 seconds to open and 21 to close, both being longer times than Audi claims.

The interior is exactly what we’ve come to expect of an Audi in 2018, with high quality materials and plenty of fancy trim. Our test car wore a beautiful arrangement of quilted Magma Red leather, glossy carbon-fiber inlays, soft-touch door panels, and premium metal accents. The layout is streamlined and clean, with everything logically placed and located. The buttons and dials feel great, and the fit and finish is top-shelf.

Our Ibis White S5 tacked on $7350 worth of extras, the costliest being the Navigation and S Sport packages. The $2500 S Sport package brought the torque-vectoring rear differential, sport-tuned adaptive damping, and red brake calipers. The $2600 Navigation pack adds Audi’s MMI Navigation Plus with MMI Touch, Audi Connect Prime and Plus services, and the 12.3-inch Virtual Cockpit digital instrument panel. A Bang & Olufsen sound system added another $950, the five-spoke 19-inch wheels and summer tires were an extra $800, and $500 worth of carbon fiber trim in the cockpit capped the options list.

That puts this S5 cabriolet at an as-tested price of $70,625. When considering the value that the A5 cabriolet offers, that’s awfully steep. The A5 might only offer a four-cylinder, but it’s capable enough to be stimulating, and the seven-speed dual-clutch gearbox is the better choice for driver engagement than the conventional eight-speed automatic in the S5. The S5 burned fuel at a 21-mpg average during our testing while the A5 returned 25 mpg, so there would be lower operating costs, as well. You need to step up to the S5 to get the high-performance hardware such as the available sport differential and adaptive damping, but if that’s your highest priority, perhaps you’d be better off ditching the ragtop and looking at the S5 coupe or Sportback models instead.

Specifications >

VEHICLE TYPE: front-engine, all-wheel-drive, 4-passenger, 2-door convertible

PRICE AS TESTED: $70,625 (base price: $63,275)

ENGINE TYPE: turbocharged and intercooled DOHC 24-valve Miller-cycle V-6, aluminum block and heads, direct fuel injection

Displacement: 183 cu in, 2995 cc
Power: 354 hp @ 6400 rpm
Torque: 369 lb-ft @ 1370 rpm

TRANSMISSION: 8-speed automatic with manual shifting mode

DIMENSIONS:
Wheelbase: 108.9 in
Length: 184.7 in
Width: 72.7 in Height: 54.4 in
Passenger volume: 86 cu ft
Trunk volume, top up/down: 9/7 cu ft
Curb weight: 4187 lb

C/D TEST RESULTS:
Zero to 60 mph: 4.8 sec
Zero to 100 mph: 12.4 sec
Zero to 130 mph: 23.3 sec
Zero to 150 mph: 37.0 sec
Rolling start, 5–60 mph: 6.1 sec
Top gear, 30–50 mph: 3.2 sec
Top gear, 50–70 mph: 4.0 sec
Standing ¼-mile: 13.5 sec @ 103 mph
Top speed (governor limited, mfr's claim): 155 mph
Braking, 70–0 mph: 158 ft
Roadholding, 300-ft-dia skidpad: 0.94 g

C/D FUEL ECONOMY:
Observed: 21 mpg
75-mph highway driving: 32 mpg
Highway range: 490 mi

EPA FUEL ECONOMY:
Combined/city/highway: 23/20/29 mpg