The M8 Gran Coupe only comes one way, so we’d recommend several options to maximize on both its luxury and performance. We’d select the Comfort Seating package that brings remote start, multiple heated surfaces, and retractable shades for the back seat. The optional carbon-ceramic brakes add cred to the M in front of the Gran Coupe’s 8 and better withstand the abuse of a track day. Speaking of racetrack action, we’d recommend the M Driver’s pack, which includes a day of professional training to learn how to safely exploit the M8’s talents and maybe briefly forget how much it costs. Choosing the latter option also raises its electrically limited top speed from 155 to 190 mph.

Engine, Transmission, and Performance

The M8 Gran Coupe is powered by a lusty twin-turbo 4.4-liter V-8 that makes 617 horsepower, thanks to the adoption of the previously optional Competition package. The exceptionally smooth engine sends that power to all four wheels via a responsive eight-speed automatic transmission. However, tail-out antics are made possible by a selectable rear-wheel-drive mode that routes all the V-8’s fury to the back. This rocket-powered four-door shot to 60 mph in just 2.7 seconds and completed the quarter-mile in 10.8 ticks at 129 mph. These numbers are impressive for some supercars, let alone a sedan that weighs more than 4300 pounds. While it’s furiously quick and provides more than 1.0 g of cornering grip, the big M8 suffers from indifferent steering feel and a stiff ride that compromises its comfort. A specially tuned adaptive suspension comes standard, and it can be adjusted through the sedan’s customizable or preset drive modes, but even the softest damper setting isn’t soft at all. Its strong brakes will haul it down from 70 mph in an impressively short 147 feet, but the Bimmer’s brake-by-wire system returned uneven responses through the pedal, regardless of the two available brake settings­ (Comfort and Sport).

Fuel Economy and Real-World MPG

With estimates of 15 mpg in the city and 22 mpg on the highway, the V-8-powered M8 Gran Coupe certainly won’t be confused for a hybrid. However, those figures are on par with other fast four-doors in this fast-sedan class, such as the Audi RS7 (15 mpg city, 22 highway). We haven’t tested the M8 Gran Coupe on our 75-mph highway fuel-economy route, which is part of our extensive testing regimen, but when we get the chance we can evaluate its real-world mpg. For more information about the M8 Gran Coupe’s fuel economy, visit the EPA’s website.

Interior, Comfort, and Cargo

The M8 Gran Coupe features an exquisitely appointed interior that looks as rich as it feels. While the design is more dignified than dazzling, the four-door M8 provides reasonable rear passenger space. It also offers a cornucopia of desirable standard features such as a 12.3-inch digital gauge cluster, 16-way power front seats with memory settings, heating, and ventilation, four-zone climate control, leather upholstery, and more. Buyers can also enhance the cabin with novel color schemes and fancy trims as well as a Comfort Seating package. This adds heated seats throughout along with power sunshades for rear-seat passengers. Likewise, the lightweight M Carbon front seats are optional, but their stiff lower side bolsters make ingress and egress a pain, and they might be generally too aggressive for most drivers. While the back seat features three seatbelts–unlike the rear buckets in the GT63 S–the middle seat is best left unoccupied except for all but the shortest trips. The Gran Coupe’s trunk provides 11 cubic feet of storage space, but that’s 15 cubes less than the volume under the RS7’s rear hatch.

Infotainment and Connectivity

Every M8 Gran Coupe is equipped with a 12.3-inch touchscreen infotainment system that can also be operated with a rotary controller on the center console. Along with its 16-speaker Harman/Kardon sound system, the brawny BMW has a Wi-Fi hotspot and Apple CarPlay and Android Auto as standard. Those who aren’t satisfied with the default audio unit can upgrade to a more powerful Bowers & Wilkins setup.

Safety and Driver-Assistance Features

While copious driver-assistance technology is available, everything except forward-collision warning and automated emergency braking costs extra. For more information about the M8 Gran Coupe’s crash-test results, visit the National Highway Traffic Safety Administration (NHTSA) and Insurance Institute for Highway Safety (IIHS) websites. Key safety features include:

• Available adaptive cruise control with stop-and-go technology
• Available blind-spot monitoring and rear cross-traffic alert
• Available lane-departure warning and lane-keeping assist

Warranty and Maintenance Coverage

BMW provides a competitive limited and powertrain warranty compared with luxury rivals’ plans. It also makes Mercedes-AMG look bad by providing complimentary scheduled maintenance.

• Limited warranty covers four years or 50,000 miles
• Powertrain warranty covers four years or 50,000 miles
• Complimentary maintenance is covered for three years or 36,000 miles

More Features and Specs