Porsche 718 Cayman GT4 RS vs BMW M4 CSL
Compare the Porsche 718 Cayman GT4 RS vs BMW M4 CSL. The BMW M4 CSL is £33,315 cheaper. The Porsche 718 Cayman GT4 RS is 0.2s quicker to 60mph. The BMW M4 CSL is more fuel efficient. Full performance, cost & ownership breakdown.
The Porsche 718 Cayman GT4 RS is priced from £115,000, powered by a 4.0L Flat-6, producing 493 hp, with 450 Nm of torque, reaching 0-60 mph in 3.4s, a top speed of 196 mph, sent to the road via rear-wheel drive. The BMW M4 CSL is priced from £74,685, powered by a 3.0L Twin-Turbo I6, producing 543 hp, with 650 Nm of torque, reaching 0-60 mph in 3.6s, a top speed of 191 mph, sent to the road via rear-wheel drive.
The Porsche 718 Cayman GT4 RS offers a 125-litre boot, a usable front boot, runs on petrol, returns around 23 mpg, is covered by a 4yr / 50k mi warranty. The BMW M4 CSL offers a 440-litre boot, runs on petrol, returns around 25 mpg, is covered by a 3yr / unlimited mi warranty.
On cost of ownership, the BMW M4 CSL is £33,315 cheaper than its rival, both require around £1,300 per year in maintenance, the BMW M4 CSL is the more fuel-efficient choice, a full tank costs around £70 for the Porsche 718 Cayman GT4 RS and £75 for the BMW M4 CSL.
Driving Character: Porsche 718 Cayman GT4 RS vs BMW M4 CSL
The Porsche 718 Cayman GT4 RS represents the apex of the 718 platform, transplanting a 493hp naturally aspirated flat-six from the GT3 into a mid-engine chassis. The result is a machine with staggering agility and a turn-in response that makes even the standard GT4 feel soft. The chassis balance is dominated by rear-end grip and sharp, responsive steering that provides constant feedback. It is an extreme instrument, demanding a high level of expertise to truly extract its full potential. The power delivery is frenetic, culminating in a high-revving wail that defines the car's racing-inspired character.
The M4 CSL represents the pinnacle of track-focused engineering for the current generation. Stripped of weight and tuned for maximum response, the chassis feels sharper and more visceral than any standard Competition model. With 543 horsepower routed solely to the rear wheels, traction management is critical, requiring a precise, disciplined approach from the driver. The steering is arguably the most communicative in the M-lineup, providing immediate feedback from the front tyres. It is a car built for circuit performance, with stiff springs and aggressive dampers that prioritise lap times and sustained performance over road-going compliance.
Head-to-head, the division is clear: the Porsche 718 Cayman GT4 RS takes our 0-100 driving character grading, 96 against 92. Characteristic of the Porsche 718 Cayman GT4 RS: GT3-derived engine in the lightest, most track-focused Cayman ever. For the BMW M4 CSL: Track-focused, lightweight M4 with the sharpest chassis in the range. In outright terms it is 493 hp against 543 — a 50 hp gap — and the Porsche 718 Cayman GT4 RS reaches 60 mph 0.2s sooner.
Interior & Cabin: Porsche 718 Cayman GT4 RS vs BMW M4 CSL
The interior is a study in weight reduction, featuring CFRP door panels, lightweight door pulls, and carbon bucket seats that lock the driver in place. The presence of the standard roll bar behind the seats signals its intent, creating a sparse, motorsport-focused atmosphere. Sound deadening is intentionally minimal, allowing the mechanical symphony—and the roar of the intake located just behind the driver's head—to flood the cabin. It is not designed for luxury or comfort, but rather as an extension of the driving experience, prioritising tactical feedback and material efficiency above all else.
The interior is a stark, focused environment designed to minimise distractions and shed weight. Carbon bucket seats are standard, offering uncompromising support, though they can be difficult to climb in and out of. Much of the typical luxury trim has been removed in favour of lightweight materials and exposed components. The dashboard still features the high-resolution curved display, ensuring the driver has access to telemetry and performance data at a glance. Legroom in the rear is minimal, effectively treating the rear bench as a shelf for track gear rather than a place for passengers.
Head-to-head, the division is clear: the BMW M4 CSL takes our 0-100 interior & cabin grading, 50 against 58. Characteristic of the Porsche 718 Cayman GT4 RS: Stripped-back, motorsport-focused cockpit. For the BMW M4 CSL: Motorsport bucket seats and minimal trim, focused on weight-saving.
Daily Usability: Porsche 718 Cayman GT4 RS vs BMW M4 CSL
Daily utility is significantly compromised by the track-oriented nature of the GT4 RS. The suspension is exceptionally firm, making it punishing on all but the smoothest road surfaces, and the lack of sound insulation makes it unsuitable for long, tedious commutes. Despite this, the front and rear trunks remain available for storage, and the inclusion of a front-axle lift system helps navigate urban obstacles. While it is technically possible to drive to the track, the RS experience is best reserved for spirited road use or dedicated circuit days rather than routine errands.
Daily utility is not the primary objective of the M4 CSL, and it shows. The low ride height and stiff suspension make navigating urban speed bumps or steep driveways a chore. While the 440-litre boot is identical to other M4 models, the lack of rear-seat utility limits its effectiveness as a family car. It is, however, perfectly capable of handling occasional motorway trips, though cabin noise from the lack of sound deadening is noticeable. For those who want a track-weapon that can legally drive to the circuit, it offers unmatched engagement, provided the compromises are accepted.
Head-to-head, the division is clear: the BMW M4 CSL takes our 0-100 daily usability grading, 35 against 45. Characteristic of the Porsche 718 Cayman GT4 RS: Usable but clearly built for track days over commuting. For the BMW M4 CSL: Usable but clearly built for track days over commuting. that means 125 litres of boot space against 440, plus a usable front boot in the Porsche 718 Cayman GT4 RS, and everyday running costs that favour the BMW M4 CSL at the pumps.
Ownership: Porsche 718 Cayman GT4 RS vs BMW M4 CSL
Owning a 718 Cayman GT4 RS is a high-stakes proposition, with high purchase prices and significant service costs reflecting its status as a low-volume, specialised performance vehicle. Values have appreciated rapidly, as the model occupies a unique space in the modern Porsche lineup. Owners benefit from the comprehensive Porsche Motorsport support network, which is essential for managing RS-specific components that are more expensive and harder to source than standard parts. It is a collector's dream, provided the owner acknowledges the substantial overheads and the demanding nature of maintaining a high-performance track machine.
Maintenance for the CSL is a premium affair, with high-performance components specifically designed for track wear. Residual values are bolstered by its limited-edition status, making it a sound long-term investment for collectors. Standard BMW servicing applies, but parts unique to the CSL, such as specific brake and chassis components, are significantly more expensive than standard M4 parts. Insurance is also likely to be higher, reflecting the performance potential and the scarcity of body panels. It is a car for the committed enthusiast who values exclusivity and track capability above all else.
Head-to-head, the division is clear: the Porsche 718 Cayman GT4 RS takes our 0-100 ownership grading, 78 against 72. Characteristic of the Porsche 718 Cayman GT4 RS: Mechanically simple, Porsche-grade reliability. For the BMW M4 CSL: Limited-run status keeps strong collector demand. On the wallet the two diverge at £115,000 versus £74,685 — a £40,315 difference, and warranty cover of 4yr / 50k mi versus 3yr / unlimited mi.