2023 Mercedes-AMG C63 S Plug-In Hybrid Returns With 671 HP

2023 Mercedes-AMG C63 S Plug-In Hybrid Returns With 671 HP

The new 2023 Mercedes-AMG C63 S E Performance has a tiny engine. With 671 hp (680 PS) on tap from its electrically-assisted 2.0 liters, it might convince you not to care that it swapped a V8 for a turbocharged four and a low-speed growl for a synthetic pedestrian warning noise.

This is a racially different hot C-Class than the ones we've known before, including the AMG C43 that downgraded from a V6 to a turbo four. When replacing a performance car generation, carmakers focus on one major change, such as all-wheel drive or a V8 downsize. 

The C63 went from a rear-wheel drive turbocharged V8 to a four-cylinder plug-in hybrid with all-wheel drive and four-wheel steering in one fell swoop.

The engine is AMG's M139L 2.0-liter inline four-cylinder seen in the SL43 and C43. Like those cars, it has an electric turbocharger, but the C63's is bigger. The SL43's gas motor has 376 hp (381 PS) and the C43 has 402 hp (408 PS), but the C63 has 470 hp (476 PS). 

This new version of the M139 is the most powerful four-cylinder production engine in the world, and with 402 lb-ft (545 Nm), it must be the torqueiest too.

That's before the 2023 electric boost. A 150 kW (201 hp / 204 PS) electric motor, a limited slip differential, and a two-speed drive unit boost the rear wheels. It can power the car as an EV at up to 78 mph (125 km/h) and for up to 8 miles (13 km), if driven gently. 

It sounds like a PHEV from a decade ago, but AMG has prioritized power over efficiency for this hybrid system.

Drawing from a 6.1 kWh battery, the motor delivers 150 kW for up to 10 seconds at a time, but always has at least 70 kW (94 hp / 95 PS), and engages its second gear from 87 mph (140 km/h) once it kisses its 13,500 rpm rev limiter.

The result is a combined gas-electric output of 671 hp (680 PS) and 752 lb-ft (1,020 Nm), making the C63 not only more powerful than the old V8-engined C63 S and its 503 hp, or the 503-hp BMW M3 Competition, but punchier than super sedans from the class above like the 617-hp BMW M5 Competition.

Zero to 100 km/h takes 3.4 seconds (down from 4.0 seconds for the old C63 S), and the 155 mph (250 km/h) top speed can be raised to 170 mph (280 km/h) with a suitable bung to your Mercedes dealer at order time.

The electric motor only drives the rear axle, and so can the gas motor. First time, all-wheel drive is default. A 9-speed epicyclic auto with a wet clutch pack replaces the torque converter in the 4Matic+ four-paw transmission.

Rear-axle steering and carbon brakes join a list of standard equipment that includes adaptive dampers for the steel-spring suspension and an AMG Dynamics drive mode selector with a new "Master" mode for oversteer antics. 

Drivers get AMG-specific graphics in the digital instrument cluster and head-up display, plus a button on the steering wheel for four levels of energy recovery, from almost none to strong enough for one-pedal driving.

A slim hood vent distinguishes the C63 from the C43, which gets a toothy Panamericana grille and flared front fenders that add 3 inches (76 mm) to the nose's width. 

The fenders have "Turbo E Performance" badges below their retro-style vents, and the hood has an AMG badge for the first time.

Everything we've said applies to the C63 wagon, which, like the new BMW M3 Touring, is likely off-limits to North American buyers. 

The long-roof version takes 3.4 seconds to hit 62 mph and rolls on 19-inch wheels unless you upgrade to 20s via an options list that includes a revised AMG Performance seat with vented side bolsters. 

The only major differences between the sedan and wagon body styles are that lifting the wagon's 155 mph speed limiter adds only 13 mph (20 km/h), not 19 mph (30 km/h), and the wagon weighs 75 lbs (34 kg) more.

The new bigger body, hybrid kit, and AWD transmission destroy that dream. The last C63 S weighed 3,704 lbs (1,680 kg) in European trim, but this one is 4,489 lbs (2,036 kg). That's like driving an old car with three or four fat friends. 

The new car is faster, greener (156 g/km vs 196 g/km), and will use less fuel (34 mpg U.S. / 41 mpg UK on the EC cycle, says AMG), but you have to wonder how the extra ballast will affect handling.

To cut weight, wait for the non-S C63. Mercedes is likely to compete with non-competition versions of the BMW M3, but downgrading will reduce horsepower and won't make it as light as a previous-generation C63.

Mercedes hasn't released pricing details for the 2023 C63 AMG, but we expect it to be close to the $80,800 BMW M3 Competition xDrive.