Thirty cars. All sold before a single person outside AMG’s Affalterbach headquarters had seen one. That is the entire commercial story of the Mercedes-AMG CLE 646 Spezialanfertigung, a hand-built, wide-body, rear-drive coupe that takes the CLE Coupe platform and rebuilds it as something closer to a road-legal racing car than a luxury grand tourer.
The CLE 646 Spezialanfertigung is the second model in the Mercedes-Benz Mythos Series, the brand’s designation for genuinely scarce collector vehicles. The first was the AMG PureSpeed, limited to 250 examples and built without a roof or windscreen. The CLE 646 goes further in the other direction: it has a roof, rear seats deleted, roll bar fitted, and a singular obsession with lap times and corner-exit angles that the PureSpeed, for all its drama, never quite claimed.
637 HP, One Driven Axle
The engine is AMG’s M177 EVO 4.0-liter V8 biturbo in its most developed form, producing 637 hp at 6,000–6,250 rpm and 627 lb-ft of torque across a broad 2,500–4,500 rpm band. A flat-plane crankshaft reduces rotating mass and sharpens throttle response. Three separate cooling circuits manage thermal loads: one high-temperature loop for the engine block, and two low-temperature circuits handling charge air, transmission oil, and the 48-volt components. An integrated starter generator (ISG) contributes an additional 23 hp and 151 lb-ft. The exhaust is a bespoke high-flow unit developed with Akrapovič, using titanium extensively to save weight while delivering what AMG describes as an emotionally engineered V8 sound signature.
Critically, none of that power goes to the front axle. AMG removed the Performance 4MATIC+ all-wheel-drive system entirely. An electronically controlled limited-slip rear differential manages torque distribution between the rear wheels, enabling variable locking action suited to everything from corner entry stability to driver-requested oversteer. Launch Control has been recalibrated for the rear-drive layout. The result: 0–62 mph in 3.9 seconds, 0–124 mph in 11.4 seconds, 0–186 mph in 36.8 seconds in Street mode and 36.2 in Race mode, and a 193-mph top speed. Power goes through an AMG SPEEDSHIFT TCT 9-speed transmission with a double-declutch downshift function.
Compare that baseline to the CLE 53 Coupe, which starts at $74,300 and makes 443 hp from a turbocharged inline-six. The 646 Spezialanfertigung is a fundamentally different machine built on the same platform, not a more aggressive tune of the same car.
Chassis, Aero, and the Business of Going Wide
AMG widened the bodyshell by 2.4 inches at both the front and rear tracks, reinforced the structure with an integrated roll bar, and lowered ride height 0.9 inches at the front and 0.6 inches at the rear. Curb weight sits at 4,178 lbs, roughly 375 lbs lighter than the donor vehicle after extensive deletion of comfort equipment, acoustic insulation, the rear seat, and various assistance systems. Weight distribution is 56 percent front, 44 percent rear.
The suspension is a purpose-developed steel coilover system jointly engineered by Mercedes-AMG and KW automotive, featuring four-way adjustable dampers with independent low-speed and high-speed compression and rebound settings. Low-speed settings govern body motion during braking and turn-in; high-speed settings handle wheel response over bumps and surface irregularities. The forged AMG Performance wheels measure 11 x 20 inches at the front and 12 x 20 inches at the rear, wearing 305/30 ZR 20 and 335/30 ZR 20 tires. The tire specification is derived from technology originally developed for the Mercedes-AMG ONE.
Braking comes from an AMG Ceramic High-Performance Composite system. Front rotors measure 16.5 x 1.6 inches, paired with six-piston fixed calipers. Rear rotors are 14.2 x 1.3 inches with single-piston floating calipers. The gold-painted calipers are the only ornamental detail on an otherwise entirely functional piece of hardware. A dedicated brake-cooling concept routes air through large front bumper intakes and purpose-designed duct elements.
The aerodynamics package is adjustable and designed around two operating modes. The front diffuser mounts via three fasteners in either Street or Race position; in Race trim it forms an inverted wing profile that generates the Venturi effect and increases front-axle downforce measurably. Channel systems beside the headlights direct air through the wheel arches and out through fender louvers, adding downforce while simultaneously venting brake heat. The center section of the carbon fiber rear wing is manually adjustable to balance rear-axle load with the front diffuser setting. A flat floor with longitudinal fins accelerates underbody airflow. Total system downforce exceeds 550 lbs at top speed, achieved at the cost of a drag coefficient that moves from 0.402 in Street trim to 0.417 in Race trim.
Carbon fiber appears throughout the exterior: widened front fenders with integrated louvers, front fascia, sill panels, hood with central cold-air intake, roof, rear apron with diffuser, trunk lid, and rear wing. Rear side glass and the rear window are polycarbonate.
Inside: Less Is the Point
The interior removes anything that isn’t about driving. Rear seats are gone. Acoustic insulation is gone. The sound system has been simplified. The number of steering wheel controls has been reduced because the drive modes and assistance systems those buttons managed no longer exist, including the PARKTRONIC parking assistant. What remains: ultra-lightweight carbon fiber door panels, a microfiber steering wheel with a motorsport-spec flattened bottom, and high-bolster racing bucket seats fitted as standard. The roll bar serves both structural and safety functions. Six-point harnesses are available as part of an optional Performance Package.
AMG TRACTION CONTROL, calibrated specifically for this car, provides nine stages of rear-axle slip adjustment for circuit use with ESP switched off. It is the primary driver aid once the stability systems are disabled, allowing precise modulation of available grip as tire temperatures build through a session.
Paint is a split-finish exclusive: Mojave Silver Magno on the front section, Obsidian Black Magno from the B-pillar rearward. AMG crests on the doors. Overall dimensions are 194.8 inches long, 78.2 inches wide, and 55.9 inches tall, on a 113.2-inch wheelbase.
AMG built the GT 53 4-Door Coupe as a technological showcase for electrification. The CLE 646 Spezialanfertigung is the counterargument: a V8, two driven wheels, and the weight of everything unnecessary already on the floor of the Affalterbach shop. Thirty buyers made that argument for AMG before the car was ever shown publicly.
Mercedes-AMG CLE 646 Spezialanfertigung Photo Gallery
Source: Mercedes-Benz. Images courtesy of Mercedes-Benz.
