Mercedes-AMG experiment with four-cylinder PHEV ends

Looks like the customers have spoken, and Mercedes-AMG definitely listens to them. They don’t like the PHEV powertrain of the C 63 or GLC 63.

No great surprise then that Mercedes-AMG is calling an end on its four-pot electified experiment for its popular range toppers. The firm intends to replace it with V6 and V8 units, both with mild hybrid assistance. That’s because customers couldn’t relate to the powerplant emotionally as they did with the V8.

Read our review of the Mercedes-AMG C 63 S E Performance.

Certainly it wasn’t because it was performance shy. The petrol-electric unit made the car quicker than any C 63 prior; we recorded a 0-100 time of 3.14sec. But it was also hundreds of kg heavier. And it also just goes to show that the noise of a machine is an important component of its overall performance, at least in this category of vehicle.

The four-cylinder plug-in hybrid drivetrain propelled both the C63 and GLC 63. At the recent reveal of the Concept GT XX in Germany, an employee of the firm said that future petrol-powered Mercedes-AMG models will use a new engine. It will be a variant of the existing in-line six-cylinder engine or an all-new V8 with a flat-plane crankshaft, like that in the GT Black Series.

The insider told Autocar UK that despite it being technically advanced, the four-pot PHEV powertrain just didn’t click for traditional customers. 

The 500kW powertrain of the C63 S E Performance was unliked because of its lack of character. And customers also said the vehicle felt bloated compared with its V8 predecessor.

Another reason for axing the powertrain is the cost of engineering the four-pot to comply with imminent Euro 7 emissions regulations. These take effect next month.

Moreover, the M139 engine found use in the A-Class hatchback (AMG A 45 S 4Matic+, above) which is being discontinued. Expect the base SL 43 model, also powered by the M139 engine, to shift to a new V6 at some point too.

Mercedes-Benz Chief Technology Officer, Markus Schäfer, did say that AMG is committed to a dual-drivetrain strategy.

“The electric pillar will grow significantly. But the second pillar – hybridised internal-combustion engines – will also remain,” he said.

“AMG and Mercedes are working together on a brand-new V8 engine. That engine will support upcoming emissions regulations. There will still be six- and eight-cylinder units, all electrified with either 48V systems or full hybrid set-ups.”