Purists may knock Mercedes-AMG’s entry-level—and mushrooming—range of 43 models for watering down the brand, as they lack the hand-built engines and mad power output of AMGs with numerically higher badges. Yet even Affalterbach’s modest fettling has produced some impressive vehicles, such as the Porsche Macan–baiting GLC43 crossover and the comparison-test-winning E43 sedan. With much of the latter’s on-road goodness stuffed into the tidier and more affordable C-class, the 2017 Mercedes-AMG C43 4MATIC sedan also earns a spot on that list.
The sports sedan formerly known as the 2016 Mercedes-Benz C450 AMG, the 2017 C43 occupies the chasm between the four-cylinder Mercedes-Benz C300 and AMG’s wild, V-8–powered C63. Although this middle child’s twin-turbocharged 3.0-liter V-6 is mass-produced in a factory, it’s plenty stout—and surprisingly soulful in tone for a bent-six on a steady diet of boost. Output here is the same as it was in the C450, at 362 horsepower and 384 lb-ft of torque, the latter coming on quick and strong and achieved at just 2000 revs.
The big change for 2017 is aft of the engine compartment, where AMG has replaced the previous seven-speed automatic transmission with its new nine-speed 9G-TRONIC unit. The goal of the swap is to improve fuel economy as well as performance, and the C43 delivers on both counts. Despite weighing an additional 66 pounds, our C43 test car shot past the C450 to 60 mph (4.1 seconds versus 4.5) on its way to a 12.7-second quarter-mile blast at 110 mph—eclipsing all of its rivals and much closer to the times of the 503-hp C63 S than the 241-hp C300. The additional gear ratios combined with snappy downshifts also improve rolling acceleration from 5 to 60, 30 to 50, and 50 to 70 mph. Driven less aggressively, we observed 21 mpg overall with the C43 versus 18 in the C450, with the new car’s 29-mpg average on our 200-mile highway test loop bettering its EPA estimate by 1 mpg.
The C43’s standard 4MATIC all-wheel drive produces far less drama in corners than the rear-drive C63. The system has been tweaked with a greater rear torque bias (31/69 percent versus the previous 33/67), adding to the car’s agile feel when pushed. Stable understeer at the limit, however, remains part of the experience, which limits the C43’s maximum lateral grip to a still-respectable 0.92 g. Both our C450 and C43 test cars had the same brakes (14.2-inch rotors in front, 12.6-inchers in back) and were upgraded from their standard 18-inch wheels to 19s with staggered, high-performance run-flat summer tires, sized 225/40R-19 in front and 255/35R-19 at the rear. Which makes the switch from the C450’s Pirelli P Zeros to the C43’s Continental ContiSportContact 5 rubber largely responsible for the latter’s lengthier stop from 70 mph (171 feet to the C450’s 160).
Hurtling down a twisty back road, the C43 feels crisp and well mannered, its responses alert but not harsh and madly aggressive like the brutish C63’s. AMG’s sharper electrically assisted steering rack is direct and precise, if rather muted, and the selectable driving modes borrowed from the C63 (Eco, Comfort, Sport, Sport+, and Individual) give the chassis, drivetrain, and steering effort a sizable amount of bandwidth. The C63 also donates its thee-position adjustable dampers and some of its front suspension hardware, which give the C43 a wider front track than the C300, as well as revised suspension geometry and increased negative camber. New for 2017 is an updated three-stage stability-control system that in its sportier settings allows for a bit more sideways action at the handling limit before stepping in.
But unless you live somewhere with roads paved in glass (i.e. not our Michigan home base), the combination of stiff suspension, big wheels, and rigid run-flat tires makes the C43’s ride obnoxiously choppy for a car that, unlike the C63, is refined enough to still serve as a humble C-class luxury sedan. We’ve yet to sample a C43 on the smaller 18-inch wheels, but expect the base setup to be slightly more complaint over rough pavement.
We wish AMG also had relaxed the programming for the new nine-speed gearbox, at least in the mid-level Sport setting that we preferred most of the time. Whereas the lazier Comfort and max-attack Sport+ settings are smartly tuned for their respective missions, Sport tended to serve up some occasional jerkiness as the computer hunted for the best ratio, and it often held onto a gear too long in normal driving, forcing us to grab the right-hand paddle on the wheel for a manual upshift.
Although the C43 can at times feel like it is trying too hard to emulate its rowdier siblings, its performance pairs well with the C63-aping exterior treatment, which is handsomely contoured and lightly dusted with AMG cues. The cabin is beautifully styled and crafted as well, with fittingly supportive sport seats and a chunky AMG steering wheel. While it lacks the bigger E43’s more accommodating back seat and newer Mercedes electronics, that model is more than $20K dearer than the $52,925 C43 sedan.
Our test car heaped an additional $13K in options atop that figure, despite the C43’s already lengthy roster of standard features and amenities. The bulk of the extras were part of the $7400 Premium 4 package, which replaces the standard 7.0-inch infotainment unit with an 8.4-inch screen and adds navigation and a touchpad to the central COMAND controller. Also included is a premium Burmester audio system, adaptive LED headlights with automatic high beams, ambient interior lighting, and a fragrance dispenser. While automated emergency braking and blind-spot monitoring are standard, Premium 4 also is the only way to get adaptive cruise control, active lane-departure warning and assist that teams with the blind-spot monitor, and a more advanced Pre-Safe Plus collision-avoidance system with pedestrian detection, rear cross-traffic alert, and rear-collision protection.
Optional items on our car that we could probably live without include $1620 for leather upholstery instead of the standard MB-Tex/Dinamica materials, $1480 for a panoramic sunroof, $1090 for a Parking Assist package (a surround-view monitor with an automated parking assistant), and $850 for those 19-inch split-five-spoke wheels with performance tires.
Although we have yet to test one of this AMG’s key competitors, the new-for-2018 Audi S4, the question at this price point really comes down to either a nicely equipped C43 or an entry-level C63 with a proper AMG V-8, which starts at $66,125. Our thirst for power likely would push us toward the latter, foregoing some day-to-day civility. But the C43’s superb blend of performance and refinement means that even this milder AMG is enjoyably potent.