The 911 offers all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The M4 doesn’t offer all-wheel drive.
Both the 911 and the M4 have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, plastic fuel tanks, traction control and electronic stability systems to prevent skidding.
J.D. Power and Associates rated the 911 first among midsize premium sporty cars in their 2013 Initial Quality Study. The M4 isn’t in the top three in its category.
J.D. Power and Associates’ 2013 Initial Quality Study of new car owners surveyed provide the statistics that show that Porsche vehicles are better in initial quality than BMW vehicles. J.D. Power ranks Porsche first in initial quality, above the industry average. With 34 more problems per 100 vehicles, BMW is ranked 18th, below the industry average.
J.D. Power and Associates’ 2013 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that Porsche vehicles are more reliable than BMW vehicles. J.D. Power ranks Porsche second in reliability, above the industry average. With 39 more problems per 100 vehicles, BMW is ranked 16th.
The 911 S’ optional 3.8 DOHC 6 cyl. produces 5 more horsepower (430 vs. 425) than the M4’s 3.0 turbo 6 cyl. The 911 GT3 Coupe’s standard 3.8 DOHC 6 cyl. produces 50 more horsepower (475 vs. 425) than the M4’s 3.0 turbo 6 cyl. The 911 Turbo S’ standard 3.8 turbo 6 cyl. produces 135 more horsepower (560 vs. 425) and 110 lbs.-ft. more torque (516 vs. 406) than the M4’s 3.0 turbo 6 cyl.
The flat cylinder configuration of the boxer engine in the 911 lowers its center of gravity, enhancing handling stability. The M4 doesn’t offer a boxer engine configuration.
Regenerative brakes improve the 911’s fuel efficiency by converting inertia back into energy instead of wasting it. The M4 doesn’t offer a regenerative braking system.
The 911 RWD/Turbo/GT3’s standard fuel tank has 1.1 gallons more fuel capacity than the M4 (16.9 vs. 15.8 gallons), for longer range between fill-ups. The 911 GT3’s optional fuel tank has 7.9 gallons more fuel capacity than the M4 (23.7 vs. 15.8 gallons).
For better traction and acceleration, the 911 has larger standard rear tires than the M4 (285/35R19 vs. 275/40R18). The 911 4S/Turbo/GT3’s rear tires are larger than the largest rear tires available on the M4 (305/30R20 vs. 275/40R18).
The 911’s standard 285/35R19 rear tires provide better handling because they have a lower 35 series profile (height to width ratio) that provides a stiffer sidewall than the M4’s standard 40 series tires. The 911’s optional 295/30R20 rear tires have a lower 30 series profile than the M4’s optional 35 series tires.
For better ride, handling and brake cooling the 911 has standard 19-inch wheels. Smaller 18-inch wheels are standard on the M4. The 911’s optional 20-inch wheels are larger than the 19-inch wheels optional on the M4.
The 911 offers active sway bars, which help keep it flat and controlled during cornering, but disconnect at lower speeds to smooth the ride and offer greater off-road suspension articulation. This helps keep the tires glued to the road on-road and off. The M4 doesn’t offer an active sway bar system.
For better maneuverability, the 911 Turbo/GT3’s turning circle is 5.2 feet tighter than the M4’s (34.8 feet vs. 40 feet). The 911’s turning circle is 3.6 feet tighter than the M4’s (36.4 feet vs. 40 feet).
The Porsche 911 may be more efficient, handle and accelerate better because it weighs about 50 to 500 pounds less than the BMW M4.
The 911 is 7.7 inches shorter than the M4, making the 911 easier to handle, maneuver and park in tight spaces.
To almost totally eliminate engine vibration in the passenger area, the 911 w/Sport Chrono (except w/o Sport Chrono) has an electronically controlled liquid-filled front engine mount. A computer-controlled electric current in the liquid changes its viscosity, allowing the mount to dampen the engine completely at all RPMs. The M4 uses conventional solid rubber engine mounts.
A low lift-over trunk design makes loading and unloading the 911 easier. The 911’s trunk lift-over height is 24.3 inches, while the M4’s liftover is 26.2 inches.
The 911’s standard folding rear seats are split to accommodate bulky cargo. The M4 Convertible’s standard single piece folding rear seat is not as flexible; long cargo and a passenger can’t share the rear seat.
The 911’s optional easy entry system raises the steering wheel and glides the driver’s seat back when the door is unlocked or the ignition is switched off, making it easier for the driver to get in and out. The M4 doesn’t offer an easy entry system.
The 911’s instruments include an oil pressure gauge and a temperature gauge – which could save your engine! Often ‘idiot lights’ don’t warn you until damage has been done. The M4 does not have an oil pressure gauge.
The 911’s front and rear power windows all open or close fully with one touch of the switches, making it more convenient at drive-up windows and toll booths, or when talking with someone outside the car. The M4’s passenger windows don’t open or close automatically.
To improve rear visibility by keeping the rear window clear, the 911 offers an optional rear wiper. The M4 doesn’t offer a rear wiper.
The 911’s optional air conditioned front seats cool the driver and front passenger and help take the sting out of hot leather in Summer. The M4 doesn’t offer air conditioned front seats.
To keep a safe, consistent following distance, the 911 PDK offers an optional Adaptive Cruise Control, which alters the speed of the vehicle without driver intervention. This allows the driver to use cruise control more safely without constantly having to disengage it when approaching slower traffic. The M4 doesn’t offer an adaptive cruise control.