Porsche 718 Cayman GT4 vs Mercedes-AMG C 63
Compare the Porsche 718 Cayman GT4 vs Mercedes-AMG C 63. The Mercedes-AMG C 63 is £0 cheaper. The Mercedes-AMG C 63 is 0.4s quicker to 60mph. The Mercedes-AMG C 63 is more fuel efficient. Full performance, cost & ownership breakdown.
The Porsche 718 Cayman GT4 is priced from £84,000, powered by a 4.0L Flat-6, producing 414 hp, with 420 Nm of torque, reaching 0-60 mph in 4.2s, a top speed of 188 mph, sent to the road via rear-wheel drive. The Mercedes-AMG C 63 is priced from £55,000, powered by a 4.0L Twin-Turbo V8, producing 503 hp, with 700 Nm of torque, reaching 0-60 mph in 3.8s, a top speed of 180 mph, sent to the road via rear-wheel drive.
The Porsche 718 Cayman GT4 offers a 150-litre boot, a usable front boot, runs on petrol, returns around 25 mpg, is covered by a 4yr / 50k mi warranty. The Mercedes-AMG C 63 offers a 455-litre boot, folding rear seats, runs on petrol, returns around 26 mpg, is covered by a 3yr / unlimited mi warranty.
On cost of ownership, the Mercedes-AMG C 63 is £0 cheaper than its rival, both require around £1,100 per year in maintenance, the Mercedes-AMG C 63 is the more fuel-efficient choice, a full tank costs around £70 for the Porsche 718 Cayman GT4 and £80 for the Mercedes-AMG C 63.
Driving Character: Porsche 718 Cayman GT4 vs Mercedes-AMG C 63
The Porsche 718 Cayman GT4 is the definition of chassis purity, pairing a naturally aspirated 4.0-litre flat-six with a mid-engine layout that offers near-perfect neutrality. The 414hp delivery is linear and predictable, allowing for precise throttle modulation through technical sections of track. The manual gearbox is a highlight, featuring short, mechanical throws that engage the driver completely. While it lacks the raw top-end speed of 911-based variants, the balanced chassis and communicative steering allow it to carry immense cornering speed, making it an exceptionally rewarding tool for those who value driver input over outright power figures.
The Mercedes-AMG C 63 remains a titan of the executive performance segment, defined by its thunderous 4.0L twin-turbo V8. The engine delivers a character that is increasingly rare, offering an aggressive, theatrical soundscape that is amplified by the mechanical limited-slip differential. The rear-wheel-drive platform provides a traditional, tail-happy balance that rewards a skilled driver, though the sheer power output requires significant caution in adverse weather conditions. It is a car that thrives on the open road, where the balance of torque and power delivery can be fully exploited, making it a visceral, highly engaging piece of German engineering.
Head-to-head, the division is clear: the Porsche 718 Cayman GT4 takes our 0-100 driving character grading, 93 against 84. Characteristic of the Porsche 718 Cayman GT4: Purist mid-engined chassis balance and involvement. For the Mercedes-AMG C 63: Thunderous twin-turbo V8 with a playful, adjustable rear-drive character. In outright terms it is 414 hp against 503 — a 89 hp gap — and the Mercedes-AMG C 63 reaches 60 mph 0.4s sooner.
Interior & Cabin: Porsche 718 Cayman GT4 vs Mercedes-AMG C 63
The cabin prioritises function, stripping away unnecessary luxuries in favour of an Alcantara-lined environment that feels race-ready. The Sport Seats Plus provide excellent lateral support during spirited driving, while the minimalist dashboard design ensures the focus remains entirely on the road ahead. Given its track-focused intent, the cabin storage is sparse and the rear seating area is replaced by a structural strut brace. It is a clean, purposeful space, though some may find the lack of comfort-oriented features a challenge for long-distance touring, fitting perfectly with the model's lightweight, enthusiast-oriented persona.
Inside, the C 63 is a blend of high-end executive luxury and focused performance. The cabin features premium Nappa leather and DINAMICA materials, with AMG-specific detailing that differentiates it from the standard C-Class. The Performance seats provide excellent support during spirited driving while remaining comfortable for daily commuting. Infotainment is delivered through a high-resolution interface that is ergonomic and well-integrated. While the rear seats offer adequate space for adults, the overall interior environment feels sophisticated, maintaining a luxurious ambience that balances the car's extreme performance capabilities with the comfort expected of a premium Mercedes saloon.
Head-to-head, the division is clear: the Mercedes-AMG C 63 takes our 0-100 interior & cabin grading, 55 against 76. Characteristic of the Porsche 718 Cayman GT4: Motorsport-flavoured cabin with genuine everyday livability. For the Mercedes-AMG C 63: Flamboyant, premium-feeling cabin with supportive seats.
Daily Usability: Porsche 718 Cayman GT4 vs Mercedes-AMG C 63
Utility is a standout feature, as the combination of front and rear trunks allows for surprising storage capacity, making the GT4 a versatile choice for weekend touring. Its compact dimensions make it relatively easy to navigate through tight city streets, although the low front splitter demands care over speed bumps and steep inclines. The suspension is firm, bordering on harsh for daily use in Sport mode, though it remains composed enough for the committed driver. It manages to balance track-ready performance with sufficient real-world practicality, provided the owner is prepared for a more rigorous ride quality.
Practicality is a cornerstone of the C 63's appeal, offering a 455-litre boot that handles everyday chores with ease. In Comfort mode, the suspension softens significantly, turning the car into a compliant cruiser capable of managing motorway miles without fatigue. It is a vehicle that transitions effortlessly from a daily office commuter to a weekend sports machine. The only real trade-off for this usability is the fuel consumption, which is significant under load, and the wide wheel arches and stance that can make navigating tight city streets or multi-storey car parks an exercise in careful spatial awareness.
Head-to-head, the division is clear: the Mercedes-AMG C 63 takes our 0-100 daily usability grading, 68 against 70. Characteristic of the Porsche 718 Cayman GT4: Surprisingly civil ride and quiet cabin for a track-focused car. For the Mercedes-AMG C 63: Comfortable, well-isolated cruiser despite its firm setup. that means 150 litres of boot space against 455, plus a usable front boot in the Porsche 718 Cayman GT4, and everyday running costs that favour the Mercedes-AMG C 63 at the pumps.
Ownership: Porsche 718 Cayman GT4 vs Mercedes-AMG C 63
Porsche ownership provides a reliable and extensive dealer network, ensuring that the Cayman GT4 is well-supported throughout its life. As a naturally aspirated model, the GT4 has retained significant residual value, making it a sound financial proposition for enthusiasts. Servicing intervals are well-defined, and while specific GT4 components might require longer lead times, the mechanical robustness of the 4.0-litre engine offers peace of mind. It remains a model with a dedicated community and strong factory support, ensuring that this iteration of the Cayman will remain a coveted machine for years to come.
Owning a C 63 is a relatively straightforward experience, thanks to the vast global Mercedes dealer network and the availability of specialist support. Maintenance is predictably expensive, with high-performance components like tyres and brakes requiring frequent attention, but the overall reliability of the powertrain is well-regarded among the community. As the industry moves toward electrification, the W205 C 63's naturally aspirated-feel V8 is increasingly seen as a desirable classic, helping to stabilise residual values. It remains a benchmark for the segment, offering a combination of daily utility and performance that continues to attract a strong, loyal owner base.
Head-to-head, the division is clear: the Porsche 718 Cayman GT4 takes our 0-100 ownership grading, 78 against 66. Characteristic of the Porsche 718 Cayman GT4: Mechanically simple, Porsche-grade reliability. For the Mercedes-AMG C 63: Feels robustly screwed together. On the wallet the two diverge at £84,000 versus £55,000 — a £29,000 difference, and warranty cover of 4yr / 50k mi versus 3yr / unlimited mi.