2024 Mercedes-Benz C-Class

When Mercedes unveiled this C-Class generation, the automaker also announced it would be four-cylinder-only. While we miss the turbocharged V6 of the AMG C 43, it was really the axing of the AMG C 63 and its turbocharged V8 that hit the hardest. Would Mercedes really try to pack an inline-four under the hood of its M3-killer?

The answer is a resounding yes, but one look at the spec sheet of the 2024 Mercedes-Benz AMG C 63 S E Performance shows that it's not messing around. That doesn't exactly roll off the tongue — though we do give Mercedes credit for fitting the monikers of three of its most popular sedans in one — but this plug-in hybrid will hit 60 mph before you can say its full name out loud. Without further ado ...  

Just as the electric turbo isn't this car's only innovation, the M139l engine isn't the C 63's only power source. There's a meaty 150-kW electric motor mounted at the rear axle paired to an electronically controlled limited-slip differential and, unusually, a two-speed gearbox. The motor primarily powers the rear axle, funneling energy to the front wheels when slippage is detected.

Since electric motors develop maximum torque from zero rpm, utilizing the two-speed transmission assures there's abundant passing power when the motor is operating at high speed. This is a setup designed to prioritize performance over efficiency.

Between its two power sources, the C 63 generates a jaw-slackening maximum output of 671 hp and 752 lb-ft of torque. Note that this is only available for brief periods, as the electric motor limits its max 201-hp boost to 10-second bursts. After that, output falls to a still significant 94 hp. Mercedes says the C 63 will blitz from a standstill to 62 mph (100 kph) in 3.3 seconds. That's about half-second quicker than the old C 63, and it won't quit until it hits 174 mph.

While the C 63 is a plug-in hybrid, its 6.1-kWh battery pack is modestly sized and its 3.7-kW onboard charger isn't designed for particularly high-speed charging. Furthermore, EV range on a full charge is estimated at just 8 miles. Thankfully, there's a Hold Battery setting to preserve juice for city centers and an Electric mode for creeping out of the driveway in the early morning without firing the engine.

The C 63 isn't all about forward attack, of course. Extreme stopping and cornering performance are other AMG hallmarks, and the C 63 kicks things off with six-piston brakes up front (the rear uses a single), and we wouldn't be surprised if carbon-ceramics eventually made an appearance on the options list. On the handling side, the C 63 comes standard with adaptive dampers with three settings — Comfort, Sport and Sport + — and rear-axle steering, which tightens the turning radius at low speeds and offers increased vehicle stability at high speeds.

On track, the C 63 occasionally feels like it could use more grip than its Michelin Pilot Sport 4 S rubber can muster. But on the region's winding coastal roads, the tires' blend of stick and ride compliance is well chosen. With so much power, you might reasonably expect this sedan to be a twitchy, high-strung beast. It's not. That's partly because AWD gets all that power down smoothly and without drama, and partly because the addition of four-wheel steering results in adroit cornering.

But a key component in the C 63's newfound civility is AMG's decision to carefully silo the powertrain's boost reserves depending on drive mode. The computer won't unlock full boost outside of the car's Race mode, and you still have to carpet the pedal and push past the accelerator's kickdown detent. Even Sport+ only activates 80% boost. This car doesn't feel like it has nearly 700 horsepower because, most of the time, it doesn't.

Unfortunately, all of this means that outside of Drift mode — the hilariously rewarding tail-happy-but-controllable nature intrinsic to C 63s of yore — is utterly absent, smothered under the heavy weight of batteries and sophisticated electronics. Mercedes says the C 63 weighs 4,828 pounds, which is already over 900 pounds more than an AMG C 43.

This is further compounded by the lack of a stirring soundtrack. Yes, Sport+ and Race trigger more aggressive noises (electronically augmented sounds are piped through a series of speakers both inside and outside the car), but it's not the same. AMG engineers may blame the increasingly draconian pass-by noise regulations in various world markets, but we suspect that existing C 63 owners will nonetheless be disappointed by how straight-laced this new model sounds.

Another thing that takes a little getting used to when driving hard? Slowing down. There are various user-selectable levels of regenerative braking, from Level 0, which feels like braking in a traditional gas car, to Level 3, which is similar to the one-pedal mode found on most EVs. That's all well and good, and pedal feel is pretty good. But it can take a bit more pressure than one might expect to slow from very high speeds on track, likely an artifact of the C 63 weighing just 240 pounds less than the last Mercedes S-Class (S 580 4Matic) that we tested.

Like other current-generation C-Class models, the C 63 benefits from Benz's slick and responsive MBUX infotainment suite, which runs through a 11.9-inch portrait-oriented touchscreen. In addition to features like wireless connectivity for Apple CarPlay and Android Auto as well as a clever augmented reality overlay for navigation, the C 63 receives dedicated performance-settings menus, as well as model-specific Supersport and Track Pace layouts for the gauge cluster display. There's even a fingerprint scanner to load individual driver profiles.