Next Mercedes-AMG C63 to Forgo V-8 for I-4 Hybrid

Mercedes-AMG strives to project a greener, more environmentally friendly image with the upcoming third-generation C63 by forgoing longstanding V-8 power in favor of an advanced 4-cyl. hybrid drivetrain developing more than 500 hp.

The performance sedan will be the first in a number of new AMG models earmarked to receive an electrified version of AMG’s new turbocharged 2.0L M139 gasoline engine when it goes on sale in early 2022.

The I-4 powerplant, which makes a maximum 416 hp and 369 lb.-ft. (500 Nm) of torque in non-electrified form in the new A45 4Matic, has been engineered for longitudinal mounting as well as mild hybrid-electric boosting. This development not only will see it used by the next C63 4Matic but also, in a less heavily tuned form, as a follow-up to the turbocharged 3.0L V-6 in today’s C43 4Matic.

The new C63 is planned to be offered in sedan, coupe and convertible body styles, with the next C43 4Matic likely to be sold in sedan, coupe, convertible and wagon forms.

Other AMG models set to run the new electrified driveline include successor models to today’s GLC43 and GLC63 SUV and GLC43 and GLC63 Coupe.

Wards has been told the M139 engine will adopt a 48V integrated starter motor similar to that already used by the turbocharged 3.0L I-6 M256 unit, which powers the CLS53 4Matic+ and other recent new AMG models.

In the CLS53 4Matic+, the gearbox-mounted starter motor provides an additional 22 hp and 184 lb.-ft (250 Nm) of electric boosting. In the next C63, however, it is expected to be tuned to provide significantly more power in combination with a similar torque loading.

The new EQ Boost hybrid drivetrain will run in combination with Mercedes-Benz’s in-house-produced 9-speed torque-converter-equipped MCT Speedshift gearbox.

Nothing is official at this early stage, though Affalterbach insiders familiar with AMG’s new model plans suggest the new 4-cyl. hybrid drivetrain will match the existing second-generation C63’s V-8 in outright power at a maximum 503 hp. This despite a 50% reduction in swept capacity and cylinder count. With the benefit of electric boosting, it also has been conceived to deliver up to 553 lb.-ft. (750 Nm) of torque, 37 lb.-ft. (50 Nm) more than today’s C63 S.

Details remain scarce, though the new driveline is thought to use a lithium-ion battery of higher capacity than the 0.9-kWh unit used by the CLS53 4Matic+. It also is expected to use a more advanced energy-recuperation system that harvests kinetic energy at each wheel.

One of the new electrified driveline’s key advantages is a reduction in weight over the front axle of the new C63. At 354 lbs. (161 kg), the M139 unit weighs 107 lbs. (49 lbs.) less than the M177 engine used by today’s C63 4Matic.

Even with the addition of the hybrid architecture, including a disc-shaped electric motor and power electronics, the new powerplant’s overall weight is claimed to undercut today’s unit. Additionally, its weight is concentrated lower in a move expected to bring about a lower center of gravity for the new AMG model.

Further plans for the next C63 include a new all-wheel-drive system providing a fully variable apportioning of power front to rear. This will allow AMG to engineer the new model with rear-wheel drive properties in certain driving modes. A pure rear-wheel-drive C63 model is planned as well.

The decision to provide the C63 with 4-cyl. power apparently was driven by parent company Mercedes-Benz as part of efforts to lower fleet CO2 emissions while harnessing the engineering lessons pursued in the development of the One hybrid hypercar.