2020 BMW M4 vs. 2019 Porsche 718 Cayman

Detailed Review, Specifications & Comparison

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The M4’s lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane. The 718 Cayman doesn’t offer a lane departure warning system.

The M4 offers an optional Side and Top View Cameras to allow the driver to see objects all around the vehicle on a screen. The 718 Cayman only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.

Both the M4 and the 718 Cayman have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras and available blind spot warning systems.

The BMW M4 weighs 571 to 1221 pounds more than the Porsche 718 Cayman. The NHTSA advises that heavier cars are much safer in collisions than their significantly lighter counterparts. Crosswinds also affect lighter cars more.


BMW pays for scheduled maintenance on the M4 for 2 years and 26000 miles longer than Porsche pays for maintenance for the 718 Cayman (3/36,000 vs. 1/10,000).

There are over 82 percent more BMW dealers than there are Porsche dealers, which makes it much easier should you ever need service under the M4’s warranty.


To reliably power the ignition and other systems and to recharge the battery, the M4 has a standard 209-amp alternator. The 718 Cayman’s 120-amp alternator isn’t as powerful.

To reliably start during all conditions and help handle large electrical loads, the M4 has a standard 900-amp battery. The 718 Cayman’s 340-amp battery isn’t as powerful.

From surveys of all its subscribers, Consumer Reports’ December 2018 Auto Issue reports that BMW vehicles are more reliable than Porsche vehicles. Consumer Reports ranks BMW 3 places higher in reliability than Porsche.


The M4 has more powerful engines than the 718 Cayman:



M4 3.0 turbo 6 cyl.

425 HP

406 lbs.-ft.

M4 3.0 turbo 6 cyl.

444 HP

406 lbs.-ft.

718 Cayman 2.0 turbo 4 cyl.

300 HP

280 lbs.-ft.

718 Cayman S 2.5 turbo 4 cyl.

350 HP

309 lbs.-ft.

718 Cayman GTS 2.5 turbo 4 cyl.

365 HP

309 lbs.-ft.

718 Cayman GTS 2.5 turbo 4 cyl.

365 HP

317 lbs.-ft.

As tested in Motor Trend the BMW M4 (base engine) is faster than the Porsche 718 Cayman (automatics tested):


718 Cayman

Zero to 60 MPH

3.9 sec

4.1 sec

Quarter Mile

12.1 sec

12.5 sec

Speed in 1/4 Mile

119.1 MPH

111.2 MPH

Fuel Economy and Range

The M4 has 1.6 gallons more fuel capacity than the 718 Cayman’s standard fuel tank (15.8 vs. 14.2 gallons), for longer range between fill-ups.

Brakes and Stopping

For better stopping power the M4’s brake rotors are larger than those on the 718 Cayman:


M4 opt.


Cayman opt.

Front Rotors

15 inches

15.7 inches

13 inches

13.8 inches

Rear Rotors

14.6 inches

15 inches

11.8 inches

13.8 inches

The M4 stops shorter than the 718 Cayman:


718 Cayman

60 to 0 MPH

98 feet

100 feet

Motor Trend

Tires and Wheels

For better traction, the M4 has larger standard tires than the 718 Cayman (F:255/40R18 & R:275/40R18 vs. F:235/45R18 & R:265/45R18). The M4’s optional front tires are larger than the largest tires available on the 718 Cayman (265/30R20 vs. 245/35R20).

The M4’s standard tires provide better handling because they have a lower 40 series profile (height to width ratio) that provides a stiffer sidewall than the 718 Cayman’s standard 45 series tires. The M4’s optional tires have a lower 30 series profile than the 718 Cayman’s optional 35 series front tires.

Suspension and Handling

For a smoother ride and more stable handling, the M4’s wheelbase is 13.3 inches longer than on the 718 Cayman (110.7 inches vs. 97.4 inches).

For better handling and stability, the track (width between the wheels) on the M4 is 2.4 inches wider in the front and 2.7 inches wider in the rear than the average track on the 718 Cayman.

The M4’s front to rear weight distribution is more even (48.1% to 51.9%) than the 718 Cayman’s (44.7% to 55.3%). This gives the M4 more stable handling and braking.


The M4’s standard power retractable hardtop allows a seamless transition from an open car, to a completely sealed coupe. The 718 Cayman doesn’t offer a retractable hardtop.

As tested by Car and Driver, the interior of the M4 Coupe is quieter than the 718 Cayman:


718 Cayman

At idle

48 dB

54 dB


87 dB

88 dB

70 MPH Cruising

68 dB

76 dB

Passenger Space

The M4 has standard seating for 4 passengers; the 718 Cayman can only carry 2.

The M4 Coupe has 42.2 cubic feet more passenger volume than the 718 Cayman (90.2 vs. 48).

Cargo Capacity

A low lift-over trunk design makes loading and unloading the M4 easier. The M4’s trunk lift-over height is 26.2 inches, while the 718 Cayman’s liftover is 32.7 inches.

With its coupe or convertible body style, valet key, locking rear seatbacks and remote trunk release lockout, the M4 offers cargo security. The 718 Cayman’s hatchback body style and non-lockable remote release defeat cargo security.


The M4 offers an optional heads-up display that projects speed and other key instrumentation readouts in front of the driver’s line of sight, allowing drivers to view information without diverting their eyes from the road. The 718 Cayman doesn’t offer a heads-up display.

If the windows are left open on the M4 the driver can close them all at the outside door handle. On a hot day the driver can lower the windows from a distance using the keyless remote. The driver of the 718 Cayman can only operate the windows from inside the vehicle, with the ignition on.

The M4’s rain-sensitive wipers adjust their speed and turn on and off automatically based on the amount of rainfall on the windshield. This allows the driver to concentrate on driving without constantly adjusting the wipers. The 718 Cayman’s standard manually variable intermittent wipers have to be constantly adjusted.

Heated windshield washer nozzles are standard on the M4 to prevent washer fluid and nozzles from freezing and help continue to keep the windshield clear in sub-freezing temperatures. The 718 Cayman doesn’t offer heated windshield washer nozzles.

A power rear sunshade is optional in the M4 Coupe to help block heat and glare for the rear passengers. The 718 Cayman doesn’t offer a rear sunshade.

The M4 has a standard dual zone air conditioning allows the driver and front passenger to choose two completely different temperatures so people with different temperature preferences won’t have to compromise. This makes both the driver and front passenger as comfortable as possible. Dual zone air conditioning costs extra on the 718 Cayman.

The M4’s optional Parking Assistant can parallel park by itself, with the driver only controlling speed with the brake pedal. The 718 Cayman doesn’t offer an automated parking system.

Model Availability

The BMW M4 comes in coupe and convertible bodystyles; the Porsche 718 Cayman isn’t available as a convertible.

© 1991-2018 Advanta-STAR Automotive Research. All rights reserved.

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