The BMW M3 Convertible (E93) with the 4.0-liter V8 engine producing 420 horsepower and paired with the M DCT (Dual Clutch Transmission) represents a high-performance iteration of BMW’s iconic sports car. Produced from June 2008 to February 2010, this variant occupied the top echelon of the E93 M3 lineup, offering open-top driving with exhilarating performance. It was part of the broader E90 series (sedan, coupe, and convertible) which utilized BMW’s then-new generation of high-revving, naturally aspirated V8 engines. The E93 aimed to deliver the M3 experience in a more accessible, wind-in-your-hair format, appealing to drivers seeking both performance and luxury.
Technical Specifications
| Brand | BMW |
| Model | M3 |
| Generation | M3 Convertible (E93) |
| Type (Engine) | 4.0 V8 (420 Hp) M DCT |
| Start of production | June, 2008 |
| End of production | February, 2010 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (economy) – urban (NEDC) | 17.3 l/100 km (13.6 US mpg, 16.3 UK mpg, 5.8 km/l) |
| Fuel consumption (economy) – extra urban (NEDC) | 9.4 l/100 km (25 US mpg, 30.1 UK mpg, 10.6 km/l) |
| Fuel consumption (economy) – combined (NEDC) | 12.3 l/100 km (19.1 US mpg, 23 UK mpg, 8.1 km/l) |
| CO2 emissions (NEDC) | 293 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 5.1 sec |
| Acceleration 0 – 62 mph | 5.1 sec |
| Acceleration 0 – 60 mph | 4.8 sec |
| Acceleration 0 – 200 km/h | 17.3 sec |
| Maximum speed | 250 km/h (155.34 mph), Electronically limited |
| Emission standard | Euro 4 |
| Weight-to-power ratio | 4.4 kg/Hp, 229.5 Hp/tonne |
| Weight-to-torque ratio | 4.6 kg/Nm, 218.6 Nm/tonne |
| Power | 420 Hp @ 8300 rpm |
| Power per litre | 105 Hp/l |
| Torque | 400 Nm @ 3900 rpm (295.02 lb.-ft. @ 3900 rpm) |
| Maximum engine speed | 8400 rpm |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | S65B40A |
| Engine displacement | 3999 cm3 (244.03 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 92 mm (3.62 in.) |
| Piston Stroke | 75.2 mm (2.96 in.) |
| Compression ratio | 12:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | Double-VANOS |
| Engine oil capacity | 8.8 l (9.3 US qt | 7.74 UK qt) |
| Coolant | 11.4 l (12.05 US qt | 10.03 UK qt) |
| Kerb Weight | 1830 kg (4034.46 lbs.) |
| Max. weight | 2280 kg (5026.54 lbs.) |
| Max load | 450 kg (992.08 lbs.) |
| Trunk (boot) space – minimum | 210 l (7.42 cu. ft.) |
| Trunk (boot) space – maximum | 350 l (12.36 cu. ft.) |
| Fuel tank capacity | 63 l (16.64 US gal | 13.86 UK gal) |
| Length | 4615 mm (181.69 in.) |
| Width | 1804 mm (71.02 in.) |
| Width including mirrors | 1976 mm (77.8 in.) |
| Height | 1392 mm (54.8 in.) |
| Wheelbase | 2761 mm (108.7 in.) |
| Front track | 1540 mm (60.63 in.) |
| Rear (Back) track | 1539 mm (60.59 in.) |
| Front overhang | 805 mm (31.69 in.) |
| Rear overhang | 1049 mm (41.3 in.) |
| Drag coefficient (Cd) | 0.32 |
| Minimum turning circle | 11.7 m (38.39 ft.) |
| Drivetrain Architecture | Rear wheel drive. Internal Combustion engine. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 7 gears, automatic transmission M DCT |
| Front suspension | Spring Strut, Transverse stabilizer |
| Rear suspension | Independent multi-link spring suspension with stabilizer |
| Front brakes | Ventilated discs, 360×30 mm |
| Rear brakes | Ventilated discs, 350×24 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | Front wheel tires: 245/40 R18; 245/35 R19 Rear wheel tires: 265/40 R18; 265/35 R19 |
| Wheel rims size | Front wheel rims: 8.5J x 18; 8.5J x 19 Rear wheel rims: 9.5J x 18; 9.5J x 19 |
Powertrain & Engine Architecture
At the heart of the E93 M3 Convertible is the S65B40A 4.0-liter naturally aspirated V8 engine. This engine, a significant departure from the inline-six engines traditionally used in M3s, produces 420 horsepower at 8,300 rpm and 295 lb-ft of torque at 3,900 rpm. It features individual throttle bodies, double-VANOS variable valve timing, and a high 12:1 compression ratio. The engine utilizes multi-port fuel injection, contributing to its responsive throttle characteristics. The M DCT (M Double Clutch Transmission) is a seven-speed automated manual transmission. It offers both fully automatic and manual shifting modes, providing quick and precise gear changes. The M DCT utilizes two separate clutches, one for odd gears and one for even gears, allowing for seamless shifts without interruption in power delivery.
Driving Characteristics
The combination of the 420 hp V8 and the M DCT transmission delivers a thrilling driving experience. Acceleration from 0 to 60 mph takes approximately 4.8 seconds, and the car is electronically limited to a top speed of 155 mph. The M DCT transmission allows for both comfortable cruising and aggressive, sporty driving. In automatic mode, the transmission provides smooth shifts, while in manual mode, drivers can control gear changes via steering wheel-mounted paddles. Compared to the standard E93 335i convertible, the M3 offers significantly more power and a more focused driving experience. While the 335i prioritizes comfort and fuel efficiency, the M3 is geared towards performance enthusiasts. The M3’s suspension is also stiffer and more responsive, providing better handling and control.
Equipment & Trim Levels
The M3 Convertible was generally well-equipped, even in its standard form. Standard features included leather upholstery, power-adjustable seats, automatic climate control, a premium sound system, and xenon headlights. Optional extras included features like a head-up display, navigation system, upgraded leather, and carbon fiber interior trim. The convertible top was a power-operated retractable hardtop, providing both open-air driving enjoyment and security when closed. The interior design was largely similar to other E93 models, but with M-specific accents, such as M badging, aluminum trim, and sport seats.
Chassis & Braking
The E93 M3 Convertible features a reinforced chassis compared to the standard 3 Series convertible, designed to handle the increased power and performance. The suspension consists of a MacPherson strut front suspension and a multi-link rear suspension, both with stiffer springs and dampers than the standard car. The braking system consists of ventilated discs at all four corners, with larger rotors and more powerful calipers than the standard E93. ABS (Anti-lock Braking System) is standard. The car’s steering is a hydraulic rack-and-pinion system, providing precise and responsive steering feel.
Market Reception & Comparison
The E93 M3 Convertible was generally well-received by automotive critics. It was praised for its powerful engine, responsive handling, and luxurious interior. However, some critics noted that the convertible body style added weight, which slightly diminished the car’s handling compared to the M3 Coupe. Fuel economy was also a concern, with the car averaging around 19 mpg in combined driving. Compared to other high-performance convertibles of the time, such as the Porsche 911 Cabriolet, the M3 offered a compelling combination of performance, luxury, and practicality.
Legacy
The E93 M3 Convertible, particularly the 420 hp V8 variant, has become a sought-after vehicle among enthusiasts. The S65 V8 engine is known for its reliability and durability, although regular maintenance is essential. The M DCT transmission is also generally reliable, but can be expensive to repair if issues arise. Today, well-maintained E93 M3 Convertibles command a premium in the used car market, appealing to drivers who appreciate the unique combination of performance, luxury, and open-top driving enjoyment that this car offers. The E93 represents a high point in BMW’s convertible history, and its V8 engine is considered by many to be one of the best ever produced by the company.
