The Mini Convertible (R52) Cooper S 1.6i 16V, produced from January 2005 to August 2008, represented a significant expansion of the revived Mini brand. Building upon the success of the R50/R53 hardtop, the R52 brought open-top motoring to the new Mini lineup. This variant, powered by the supercharged 1.6-liter engine producing 170 horsepower, occupied the performance-oriented mid-range position within the Convertible series, slotting above the base Cooper models and below any potential future, more powerful iterations. The R52 generation was built on the BMW/MINI 1HX0/A3 platform, sharing many components with the contemporary Mini Cooper and Cooper S hardtops, but with unique structural reinforcements to maintain chassis rigidity after removing the roof.
Technical Specifications
| Brand | Mini |
| Model | Convertible |
| Generation | Convertible (R52) |
| Type (Engine) | Cooper S 1.6i 16V (170 Hp) |
| Start of production | January, 2005 |
| End of production | August, 2008 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 11.8 l/100 km (19.9 US mpg, 23.9 UK mpg, 8.5 km/l) |
| Fuel consumption (extra urban) | 7.1 l/100 km (33.1 US mpg, 39.8 UK mpg, 14.1 km/l) |
| Fuel consumption (combined) | 8.8 l/100 km (26.7 US mpg, 32.1 UK mpg, 11.4 km/l) |
| CO2 emissions | 211 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 7.4 sec |
| Acceleration 0 – 62 mph | 7.4 sec |
| Acceleration 0 – 60 mph | 7 sec |
| Maximum speed | 215 km/h (133.59 mph) |
| Weight-to-power ratio | 7.7 kg/Hp, 129.3 Hp/tonne |
| Weight-to-torque ratio | 6 kg/Nm, 167.3 Nm/tonne |
| Power | 170 Hp @ 6000 rpm |
| Power per litre | 106.4 Hp/l |
| Torque | 220 Nm @ 4000 rpm (162.26 lb.-ft. @ 4000 rpm) |
| Engine layout | Front, Transverse |
| Engine Model/Code | W11B16A |
| Engine displacement | 1598 cm3 (97.52 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 77 mm (3.03 in.) |
| Piston Stroke | 85.8 mm (3.38 in.) |
| Compression ratio | 8.3:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Supercharger, Intercooler |
| Valvetrain | SOHC |
| Engine oil capacity | 4.8 l (5.07 US qt | 4.22 UK qt) |
| Coolant | 6 l (6.34 US qt | 5.28 UK qt) |
| Kerb Weight | 1315 kg (2899.08 lbs.) |
| Trunk (boot) space – minimum | 120 l (4.24 cu. ft.) |
| Trunk (boot) space – maximum | 605 l (21.37 cu. ft.) |
| Fuel tank capacity | 50 l (13.21 US gal | 11 UK gal) |
| Length | 3655 mm (143.9 in.) |
| Width | 1688 mm (66.46 in.) |
| Width including mirrors | 1955 mm (76.97 in.) |
| Height | 1415 mm (55.71 in.) |
| Wheelbase | 2467 mm (97.13 in.) |
| Front track | 1460 mm (57.48 in.) |
| Rear (Back) track | 1454 mm (57.24 in.) |
| Front overhang | 647 mm (25.47 in.) |
| Rear overhang | 541 mm (21.3 in.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the front wheels of the vehicle. |
| Drive wheel | Front wheel drive |
| Number of gears and type of gearbox | 6 gears, manual transmission |
| Front suspension | Independent, type McPherson with coil spring and anti-roll bar |
| Rear suspension | Trailing arm |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
Powertrain & Engine Architecture
The heart of the Cooper S Convertible was the W11B16A 1.6-liter inline-four cylinder engine. This engine, a product of BMW’s engineering, was notable for its use of a mechanically driven supercharger, developed by Eaton. Unlike turbochargers, superchargers provide instant boost response, resulting in strong low-end torque. The engine featured multi-point fuel injection and a single overhead camshaft (SOHC) valvetrain. The supercharger, coupled with an intercooler, boosted output to 170 hp at 6000 rpm and 162 lb-ft of torque at 4000 rpm. The standard transmission was a Getrag six-speed manual, providing precise shifts and allowing drivers to fully exploit the engine’s powerband. While a six-speed automatic transmission was available, it was less common and often criticized for slightly diminishing the car’s sporty character.
Driving Characteristics
The Cooper S Convertible, with its 170 hp and relatively light weight, offered a spirited driving experience. Acceleration from 0 to 60 mph took around 7 seconds, and top speed was rated at 133.59 mph. The supercharger provided a noticeable surge of power from low engine speeds, making it easy to navigate city streets and execute quick overtaking maneuvers. Compared to the base Cooper Convertible, the Cooper S offered a significantly more engaging driving experience. The manual transmission version was particularly praised for its responsiveness. The automatic, while convenient, felt somewhat less connected and resulted in a slight performance decrease. The convertible top mechanism, while adding weight, didn’t drastically impact handling, thanks to the R52’s reinforced chassis.
Equipment & Trim Levels
The Cooper S Convertible came reasonably well-equipped as standard. Features included air conditioning, power windows and locks, a multi-function steering wheel, and a basic audio system. Upholstery was typically cloth, but leather options were available. Common optional extras included a premium sound system, heated seats, automatic climate control, and various cosmetic enhancements. The “Chili Package” was a popular option, adding sport seats, a sport suspension, and exterior styling upgrades. Interior trim options allowed for a degree of personalization, with various color combinations and materials available.
Chassis & Braking
The R52 Convertible’s chassis was based on the R50/R53 platform, but with significant reinforcement to compensate for the loss of the fixed roof. This included additional bracing in the sills and underbody. The front suspension utilized McPherson struts with coil springs and an anti-roll bar, while the rear employed a trailing arm setup. Brakes were ventilated discs at the front and solid discs at the rear. ABS (Anti-lock Braking System) was standard. The suspension tuning aimed for a balance between comfort and handling, providing a reasonably compliant ride while still offering good body control.
Market Reception & Comparison
The Mini Convertible (R52) Cooper S was generally well-received by automotive critics. It was praised for its stylish design, fun-to-drive character, and premium feel. However, some criticisms were leveled at the limited rear seat space and the relatively small trunk, especially when the top was down. Compared to other small convertibles of the era, such as the Mazda MX-5 Miata, the Cooper S offered a more luxurious and refined experience, but at a higher price point. Fuel economy was reasonable for a performance-oriented convertible, averaging around 26.7 US mpg in combined driving. Reliability was generally good, although some owners reported issues with the supercharger and electrical components.
Legacy
The R52 Cooper S Convertible played a crucial role in establishing the new Mini brand as a desirable and fashionable choice. The supercharged 1.6-liter engine proved to be a reliable and enjoyable powerplant, and many examples remain on the road today. While the R52 has been superseded by later generations of the Mini Convertible, it retains a loyal following among enthusiasts who appreciate its unique blend of style, performance, and British charm. In the used car market, well-maintained R52 Cooper S Convertibles hold their value reasonably well, particularly those with low mileage and a comprehensive service history. The W11B16A engine, while requiring regular maintenance, is generally considered durable, and parts availability remains good.
