Both the 718 Cayman and the C-Class Coupe 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, available crash mitigating brakes and blind spot warning systems.
Compare the2022 Porsche 718 CaymanVS 2021 Mercedes C-Class Coupe


Safety
Warranty
The 718 Cayman’s corrosion warranty is 7 years longer than the C-Class Coupe’s (12 vs. 5 years).
Reliability
A reliable vehicle saves its owner time, money and trouble. Nobody wants to be stranded or have to be without a vehicle while it’s being repaired. Consumer Reports rates the 718 Cayman’s reliability 22 points higher than the C-Class Coupe.
J.D. Power and Associates rated the 718 Cayman second among compact premium sporty cars in their 2021 Initial Quality Study. The C-Class Coupe isn’t in the top three in its category.
J.D. Power and Associates’ 2021 Initial Quality Study of new car owners surveyed provide the statistics that show that Porsche vehicles are better in initial quality than Mercedes vehicles. With 30 fewer problems per 100 vehicles, JD Power ranks Porsche higher than Mercedes.
J.D. Power and Associates’ 2022 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that Porsche vehicles are more reliable than Mercedes vehicles. J.D. Power ranks Porsche above average in long-term dependability. With 30 more problems per 100 vehicles in the first three years of ownership, Mercedes is rated below average.
From surveys of all its subscribers, Consumer Reports’ January 2021 Auto Issue reports that Porsche vehicles are more reliable than Mercedes vehicles. Consumer Reports ranks Porsche 11 places higher in reliability than Mercedes.
Engine
The 718 Cayman’s standard 2.0 turbo 4-cylinder produces 45 more horsepower (300 vs. 255) and 7 lbs.-ft. more torque (280 vs. 273) than the C-Class Coupe’s 2.0 turbo 4-cylinder. The 718 Cayman S’ standard 2.5 turbo 4-cylinder produces 95 more horsepower (350 vs. 255) and 36 lbs.-ft. more torque (309 vs. 273) than the C-Class Coupe’s 2.0 turbo 4-cylinder. The 718 Cayman GTS 4.0’s standard 4.0 GT3 6-cylinder produces 139 more horsepower (394 vs. 255) and 36 lbs.-ft. more torque (309 vs. 273) than the C-Class Coupe’s 2.0 turbo 4-cylinder. The 718 Cayman GT4’s standard 4.0 GT3 6-cylinder produces 159 more horsepower (414 vs. 255) and 36 lbs.-ft. more torque (309 vs. 273) than the C-Class Coupe’s 2.0 turbo 4-cylinder. The 718 Cayman GT4 RS’ standard 4.0 DOHC 6-cylinder produces 238 more horsepower (493 vs. 255) and 58 lbs.-ft. more torque (331 vs. 273) than the C-Class Coupe’s 2.0 turbo 4-cylinder.
The flat cylinder configuration of the boxer engine in the 718 Cayman lowers its center of gravity, enhancing handling stability. The C-Class Coupe doesn’t offer a boxer engine configuration.
Fuel Economy and Range
An engine control system that can shut down some of the engine’s cylinders helps improve the 718 Cayman GT4/GTS 4.0’s fuel efficiency. The C-Class Coupe doesn’t offer a system that can shut down part of the engine.
Regenerative brakes improve the 718 Cayman’s fuel efficiency by converting inertia back into energy instead of wasting it. The C-Class Coupe doesn’t offer a regenerative braking system.
Transmission
The 718 Cayman offers a manual transmission for better acceleration, control and sportiness. The C-Class Coupe doesn’t offer a manual transmission.
The 718 Cayman offers an optional sequential manual gearbox (SMG). With no clutch pedal to worry about and a fully automatic mode, an SMG is much more efficient than a conventional automatic but just as easy to drive. The C-Class Coupe doesn’t offer an SMG.
The 718 Cayman PDK’s optional launch control uses engine electronics to hold engine RPM’s precisely in order to provide the most stable and rapid acceleration possible, using all of the available traction. The C-Class Coupe doesn’t offer launch control.
Brakes and Stopping
For better stopping power the 718 Cayman GT4 CCB’s brake rotors are larger than those on the C-Class Coupe:
|
718 Cayman GT4 CCB |
C-Class Coupe |
Front Rotors |
16.1 inches |
13 inches |
Rear Rotors |
15.4 inches |
11.8 inches |
The 718 Cayman offers optional heat-treated ceramic brake rotors, which last ten to twenty times as long as conventional cast iron rotors, don’t rust, don’t fade during repeated high speed braking, and their lighter weight contribute to better braking, handling and acceleration. The C-Class Coupe doesn’t offer ceramic brake rotors.
The 718 Cayman stops much shorter than the C-Class Coupe:
|
718 Cayman |
C-Class Coupe |
|
60 to 0 MPH |
97 feet |
109 feet |
Motor Trend |
Tires and Wheels
For better traction, the 718 Cayman has larger standard tires than the C-Class Coupe (F:235/45R18 & R:265/45R18 vs. F:225/45R18 & R:245/40R18). The 718 Cayman GT4’s tires are larger than the largest tires available on the C-Class Coupe (F:245/35R20 & R:295/30R20 vs. F:225/40R19 & R:255/35R19).
The 718 Cayman GT4’s 245/35R20 front and 295/30R20 rear tires provide better handling because they have a lower 35 series front and 30 series rear profile (height to width ratio) that provides a stiffer sidewall than the C-Class Coupe’s optional 40 series front and 35 series rear tires.
For better ride, handling and brake cooling the 718 Cayman offers optional 20-inch wheels. The C-Class Coupe’s largest wheels are only 19-inches.
Suspension and Handling
The 718 Cayman offers an optional driver-adjustable suspension system. It allows the driver to choose between an extra-supple ride, reducing fatigue on long trips, or a sport setting, which allows maximum control for tricky roads. The C-Class Coupe’s suspension doesn’t offer adjustable shock absorbers.
The 718 Cayman GT4 RS handles at 1.11 G’s, while the C 300 pulls only .91 G’s of cornering force in a Car and Driver skidpad test.
The 718 Cayman GT4 executes Motor Trend’s “Figure Eight” maneuver 2.8 seconds quicker than the C 300 4MATIC (23.1 seconds @ .87 average G’s vs. 25.9 seconds @ .71 average G’s).
For better maneuverability, the 718 Cayman’s turning circle is .7 feet tighter than the C 300’s (36.1 feet vs. 36.8 feet).
Chassis
The Porsche 718 Cayman may be more efficient, handle and accelerate better because it weighs about 400 to 500 pounds less than the Mercedes C-Class Coupe.
The 718 Cayman is 1 foot shorter than the C-Class Coupe, making the 718 Cayman easier to handle, maneuver and park in tight spaces.
To almost totally eliminate engine vibration in the passenger area, the 718 Cayman w/Sport Chrono has an electronically controlled liquid-filled front engine mount and conventional liquid-filled engine mounts (standard liquid front mount on other versions of the 718 Cayman). A computer-controlled electric current in the liquid changes its viscosity, allowing the mount to dampen the engine completely at all RPMs. The C-Class Coupe uses conventional solid rubber engine mounts.
Passenger Space
The 718 Cayman has .3 inches more front headroom and .2 inches more front legroom than the C-Class Coupe.
Cargo Capacity
The 718 Cayman has a much larger trunk than the C-Class Coupe (15 vs. 10.5 cubic feet).
Servicing Ease
J.D. Power and Associates surveys of service recipients show that Porsche service is better than Mercedes. J.D. Power ranks Porsche third in service department satisfaction. With a 30% lower rating, Mercedes is ranked 18th.
Ergonomics
The 718 Cayman’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 C-Class Coupe does not have an oil pressure gauge.
To improve rear visibility by keeping the rear window clear, the 718 Cayman offers an optional rear wiper. The C-Class Coupe doesn’t offer a rear wiper.
In poor weather, headlights can lose their effectiveness as grime builds up on their lenses. This can reduce visibility without the driver realizing. The 718 Cayman has standard headlight washers to keep headlight output high. The C-Class Coupe doesn’t offer headlight washers.
Economic Advantages
The 718 Cayman will cost the buyer less in the long run because of its superior resale value. The IntelliChoice estimates that the 718 Cayman will retain 59.52% to 61.35% of its original price after five years, while the C-Class Coupe only retains 43.69% to 44.32%.
Recommendations
The 718 was chosen as one of Car and Driver’s “Top Ten” for 17 of the last 18 years. The C-Class Coupe has never been a Car and Driver “Top Ten” pick.
The 718 Cayman was chosen as one of Automobile Magazine’s “All Stars” for 3 of the last 9 years. The C-Class Coupe has never been an “All Star.”