20 MPG combined isn’t going to win any fuel efficiency awards, but for the 2019 BMW M850i xDrive Convertible, it’s almost beside the point. After all, this car isn’t bought for its lower fuel costs, but for its effortless power, stunning looks, and open-air driving experience. People who choose this car prioritize a symphony of V8 exuberance over squeezing out an extra mile per gallon.

City and highway performance

Those 20 combined MPG break down to 17 MPG in the city and a more respectable 26 MPG on the highway. The city figure reflects the inherent inefficiency of stop-and-go driving with a large displacement engine. The M850i’s 4.4L twin-turbo V8 needs a good deal of fuel to get its 4,700+ pounds moving from a standstill. However, the highway number showcases the benefits of the smooth-shifting 8-speed automatic transmission and the engine’s ability to cruise comfortably at lower RPMs. Keep the turbos spooled and your right foot planted, though, and expect that highway number to plummet quickly.

Annual fuel cost

The EPA estimates an annual fuel cost of $2,900 for the 2019 BMW M850i xDrive Convertible. This figure is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway, using national average fuel prices. While this is a considerable expense, it’s unlikely to deter the typical M850i buyer. Someone spending over $100,000 on a luxury convertible probably isn’t overly concerned about the cost of premium gasoline.

Real-world expectations

The EPA figures provide a useful baseline, but real-world MPG will vary based on driving style and conditions. A lead-footed driver enjoying the M850i’s performance potential can expect to see significantly lower numbers, possibly dipping closer to 15 MPG overall. Conversely, someone employing a very gentle driving style on mostly highway miles might achieve figures closer to 28 MPG. The key to maximizing fuel economy in this car is resisting the temptation to fully unleash its power, a challenge for many who own one.

How it compares

Compared to other luxury convertibles in its class, the M850i’s fuel economy lands somewhere in the middle of the pack. The Mercedes-AMG SL63, with its similar performance profile, achieves around 16 MPG city and 24 MPG highway. The Porsche 911 Carrera S Cabriolet fares somewhat better, achieving around 18 MPG city and 25 MPG highway thanks to its smaller engine and lighter weight, but it’s a different driving experience altogether. Stepping outside the convertible segment, you might consider a BMW M5 sedan. It offers comparable performance and practicality, while achieving similar fuel economy numbers (15 MPG city, 21 MPG highway). The trade-off, of course, is the open-air experience that the M850i delivers. For those considering this BMW, it is more important to understand the M850I MPG across all years rather than compare its fuel economy data across other vehicles.

Tips to maximize efficiency

Engage Eco Pro mode. The M850i offers various driving modes, and Eco Pro prioritizes fuel efficiency by adjusting throttle response, shift points, and climate control settings. It might slightly dull the performance, it can make a noticeable difference in fuel consumption, especially during city driving.

Maintain a steady speed on the highway. Using cruise control or simply being mindful of maintaining a consistent throttle position helps avoid unnecessary acceleration and deceleration, which consume more fuel. Anticipating traffic flow and avoiding sudden braking can also improve efficiency. Keeping up to date on all Bmw fuel economy data can help you with all of your automotive decisions.

Ensure proper tire inflation. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressures regularly and inflate them to the recommended levels specified on the driver’s side doorjamb.

Avoid excessive idling. Letting the engine idle for extended periods wastes fuel. If you’re waiting for someone or anticipating a delay, turn off the engine. Modern engines do not require extensive warm-up periods, so starting and stopping the engine is more efficient than idling, especially after the engine has reached operating temperature.

Lighten the load. Carrying unnecessary weight in the car reduces fuel economy. Remove any items from the trunk or passenger compartment that aren’t essential. Every extra pound adds to the engine’s workload, especially during acceleration.