According to Autocar, AMG is targeting over 700 hp and 884 lb-ft of torque from a modified inline-six and a hybrid system for its M5 rival. No car in that class has run a straight six since the mid-Nineties.
Mercedes-Benz
Big changes are happening at Mercedes-AMG. Reconciling increasingly strict fuel-economy and emissions standards with desires for more power, AMG is on an electrification and downsizing kick. So far, the new AMG C63 has ditched its beloved V-8 for a 2.0-liter turbo four-cylinder with an electric motor at the rear axle. The next E63 may take a similar approach.
According to Autocar, the next E63 will dump its V-8 for a 3.0-liter turbocharged straight-six paired with AMG’s E-Performance plug-in hybrid system. The ‘six is reportedly a heavily reworked version of the Mercedes M256, used in a variety of models including AMG’s 53-series cars. It makes 429 hp and 384 lb-ft of torque thanks in part to an exhaust-driven turbocharger and what Mercedes calls an “electric auxiliary compressor,” which is essentially a supercharger powered by an electric motor rather than by a belt. We could imagine the AMG-reworked M256 could get an electric turbocharger like the M139 four-cylinder in the C63.
AMG’s hybrid system consists of a 6.1-kWh battery mounted above the rear axle, which an electric motor that outputs 201 hp and 236 lb-ft. The motor is connected to a two-speed gearbox with an integrated limited-slip differential and sends power to all four wheels, though in most scenarios, it only drives the rear axle. Autocar reports that AMG is targeting over 700 hp and 884 lb-ft of torque, so presumably it’s looking to get over 500 hp from the straight-six alone. That should be fairly easy for AMG, considering it gets 476 hp from the four-cylinder in the C63.
It will be a couple years before we see the new E63, as the W214-chassis E-Class on which it’s based hasn’t even debuted yet.
The E34 M5.
BMW
What’s interesting here is that this will be the first time a car in this rarefied category will have straight-six power. In the Nineties, AMG made a six-cylinder version of the W210-chassis E-Class, the E36, though it was sold in exceedingly limited numbers. The last real example of a straight-six super sedan was the E34-chassis BMW M5, which ended production in 1996. The C63’s move to four-cylinder power was controversial, though I suspect enthusiasts will be more receptive to a six-cylinder E63.
Chris Perkins Senior Editor Chris Perkins is the Web Editor for Road & Track magazine.
Keyword: The Next Mercedes-AMG E63 May Ditch Its V-8 For a Straight-Six, a First Since the Nineties