The automotive world is buzzing with news from Stuttgart. Mercedes-AMG has made a significant decision regarding the future of its compact performance sedan. The upcoming 2026 Mercedes-AMG C63 will feature a brand new powertrain, replacing the current hybrid system built around a four-cylinder engine that has struggled to win over traditional AMG enthusiasts.
A few years back, Mercedes shocked the industry by introducing what they claimed was the world’s most powerful four-cylinder engine – delivering a mind-blowing 680 horsepower with electric assistance in the current C63 AMG. But plans have changed for the next generation model, as sales numbers haven’t matched the company’s expectations.
Saying goodbye to the four-cylinder in the 2026 C63 AMG
According to industry reports, Mercedes has decided to abandon the 2.0-liter four-cylinder engine in the next C63 AMG. What will replace it? The German automaker will instead utilize a new 3.0-liter twin-turbocharged inline-six engine.
This configuration is similar to what Mercedes already employs in other models like the E53, but the C63 version will be substantially more powerful. And that’s not the only change planned – the current rear-mounted electric motor will be repositioned between the engine and transmission in the updated design.
British automotive sources suggest the total power output might reach around 659 horsepower with 650 lb-ft of torque. While these figures would actually represent a slight decrease from the current model’s specs, the final numbers aren’t set in stone yet. (Honestly, do we really need to split hairs over 20 horsepower when we’re already dealing with supercar levels of power?)
This powertrain change is part of a broader refresh planned for next year, and the new drivetrain will also find its way into the 2027 GLC 63 crossover model.
Why a V8 isn’t coming back
While six cylinders certainly sound better than four, many AMG fans were hoping for the glorious return of the V8. Unfortunately for these enthusiasts, fitting a 4.0-liter twin-turbo eight-cylinder engine into the C-Class platform is simply not feasible due to both space constraints and emissions regulations.
Sources familiar with the matter state that installing a V8 would require “major structural changes” along with “a new round of crash tests and regulatory approval.” This argument makes sense given that the fifth-generation C-Class debuted over four years ago, and its successor is already on the horizon.
Not all hope is lost for V8 lovers, though. The upcoming CLE 63 model will still feature an eight-cylinder engine, preserving that distinctive V8 rumble somewhere in the Mercedes lineup.
The world’s most powerful four-cylinder – an engineering masterpiece
The current C63 AMG’s propulsion system is truly a technological marvel, even if many of us still prefer the classic V8 growl. It combines a gasoline engine with an electric motor for impressive performance.
Designated as M139L, the longitudinally-mounted four-cylinder features an electrically-assisted turbocharger – the first production car to utilize this Formula 1-derived technology previously employed by the Mercedes-AMG F1 team.
The main advantage of an electric turbocharger is its immediate response across the entire engine speed range. With just four cylinders and 2.0 liters of displacement, this powerplant produces 476 horsepower and 402 lb-ft of torque, making it the most powerful four-cylinder on the market today.
This combustion engine works in tandem with a 204-horsepower electric motor that adds another 236 lb-ft of torque. Together, they deliver a combined output of 680 horsepower and 752 lb-ft of torque. Have you ever imagined a compact sedan with more power than many supercars? That’s exactly what Mercedes created.
The system also includes a 6.1 kWh lithium battery providing about 8 miles of electric-only range. While this isn’t enough for a zero-emissions rating in the US, it still qualifies for partial tax benefits in many states.
Paired with a nine-speed AMG SPEEDSHIFT MCT automatic transmission and the AMG Performance 4MATIC+ all-wheel-drive system, the current C63 accelerates from 0-60 mph in just 3.3 seconds. Its top speed is electronically limited to 174 mph, though this can be raised to 174 mph with the optional AMG Driver’s Package.
Why the change of heart?
Despite its technological prowess, the four-cylinder C63 hasn’t resonated with traditional AMG customers. Many buyers in this segment are looking for not just raw performance numbers but also a certain character and driving experience that’s deeply linked to engine configuration and sound.
The move to an inline-six represents a middle ground between modern efficiency requirements and the emotional appeal that drives sales in the performance segment. With six cylinders, Mercedes hopes to recapture some of the magic that made previous AMG models so desirable while still moving forward with partial electrification.
Would you consider the upcoming six-cylinder C63, or are you among those who won’t settle for anything less than eight cylinders? The performance car landscape is changing rapidly, and automakers like Mercedes are trying to find the right balance between tradition and innovation.
Whatever your preference, one thing remains clear – the AMG division continues to push the boundaries of what’s possible in performance engineering, even as they adapt to changing market conditions and regulatory requirements.
