The Alpina B3 Cabrio (E36) 3.0i 24V with SwitchTronic transmission, produced between 1994 and 1996, represents a unique blend of open-air motoring and high-performance engineering from the renowned Bavarian automaker. Built on the foundation of the BMW E36 3-Series Cabriolet, the B3 was Alpina’s take on a refined, yet potent, grand tourer. It occupied a niche position above the standard 3-Series convertibles, offering a more exclusive experience with enhanced performance and luxurious appointments. This variant, equipped with the 3.0-liter inline-six engine and the SwitchTronic automatic gearbox, aimed to deliver a balance between spirited driving and comfortable cruising.
Technical Specifications
| Brand | Alpina |
| Model | B3 |
| Generation | B3 Cabrio (E36) |
| Type (Engine) | 3.0i 24V (250 Hp) SwitchTronic |
| Start of production | 1994 |
| End of production | 1996 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (combined) | 9.7 l/100 km |
| Fuel consumption (US mpg) | 24.2 US mpg |
| Fuel consumption (UK mpg) | 29.1 UK mpg |
| Fuel consumption (km/l) | 10.3 km/l |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 6.8 sec |
| Acceleration 0 – 62 mph | 6.8 sec |
| Acceleration 0 – 60 mph | 6.5 sec |
| Maximum speed | 251 km/h (155.96 mph) |
| Weight-to-power ratio | 5.8 kg/Hp |
| Power | 250 Hp @ 5700 rpm |
| Power per litre | 83.4 Hp/l |
| Torque | 320 Nm @ 4400 rpm (236.02 lb.-ft. @ 4400 rpm) |
| Engine layout | Front, Longitudinal |
| Engine displacement | 2997 cm3 (182.89 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 86 mm (3.39 in.) |
| Piston Stroke | 86 mm (3.39 in.) |
| Compression ratio | 10.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Kerb Weight | 1450 kg (3196.7 lbs.) |
| Max. weight | 1895 kg (4177.76 lbs.) |
| Max load | 445 kg (981.06 lbs.) |
| Trunk (boot) space – minimum | 230 l (8.12 cu. ft.) |
| Fuel tank capacity | 65 l (17.17 US gal | 14.3 UK gal) |
| Length | 4433 mm (174.53 in.) |
| Width | 1710 mm (67.32 in.) |
| Height | 1328 mm (52.28 in.) |
| Wheelbase | 2700 mm (106.3 in.) |
| Front track | 1410 mm (55.51 in.) |
| Rear (Back) track | 1423 mm (56.02 in.) |
| Minimum turning circle | 10.4 m (34.12 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears | 5 |
| Gearbox type | automatic transmission SwitchTronic |
| Front suspension | Wishbone |
| Rear suspension | Coil spring |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system), Hydraulic Steering |
| Tires size | 235/40 R17; 265/35 R17 |
| Wheel rims size | 17 |
Powertrain & Engine Architecture
At the heart of the B3 Cabrio 3.0i lies Alpina’s version of the BMW M30 inline-six engine. Displacing 3.0 liters (2997 cc), this engine produced 250 horsepower at 5700 rpm and 320 Nm (236 lb-ft) of torque at 4400 rpm. Alpina didn’t simply drop the M30 into the E36 chassis; they meticulously tuned it for enhanced drivability and reliability. Key modifications included high-compression pistons, a specially designed cylinder head with optimized porting, and a lightweight flywheel. The engine utilized a Bosch Motronic fuel injection system and a dual overhead camshaft (DOHC) valvetrain, contributing to its smooth power delivery. The “SwitchTronic” transmission was a four-speed automatic gearbox developed in collaboration with ZF. It offered both fully automatic operation and a manual shift mode, allowing drivers to exert more control over gear selection. This transmission was specifically calibrated to complement the engine’s characteristics, providing smooth shifts and responsive acceleration.
Driving Characteristics
The B3 Cabrio 3.0i with SwitchTronic offered a distinctly different driving experience compared to the standard E36 Cabriolet or even the higher-performance M3. While not as overtly aggressive as the M3, the B3 provided ample power for spirited driving. The 0-60 mph sprint took approximately 6.5 seconds, and the car could reach a top speed of 156 mph. The SwitchTronic transmission, while not as quick as a manual gearbox, offered a good balance of convenience and control. The automatic mode provided relaxed cruising, while the manual mode allowed drivers to downshift for more aggressive cornering or overtaking. The gear ratios were tuned to prioritize mid-range torque, making the car feel responsive in everyday driving situations. Compared to the six-speed manual M3, the B3 felt more refined and less demanding, appealing to drivers who prioritized comfort and ease of use.
Equipment & Trim Levels
The Alpina B3 Cabrio was positioned as a premium offering, and its equipment levels reflected this. Standard features included leather upholstery, heated front seats, power windows and locks, and an upgraded sound system. Alpina-specific touches were evident throughout the interior, including unique wood trim, Alpina-branded gauges, and a special steering wheel. Optional extras included a sunroof, automatic climate control, and a premium audio system. The exterior also featured subtle but distinctive Alpina styling cues, such as a unique front spoiler, rear spoiler, and Alpina-specific wheels. The interior trim was typically more luxurious than the standard BMW offerings, with a focus on high-quality materials and craftsmanship.
Chassis & Braking
The B3 Cabrio retained the E36’s MacPherson strut front suspension and multi-link rear suspension, but Alpina made subtle modifications to the suspension tuning to improve ride comfort and handling. The springs and dampers were recalibrated to provide a more compliant ride without sacrificing stability. The B3 featured ventilated disc brakes at the front and solid disc brakes at the rear. Anti-lock braking system (ABS) was standard. The car rode on 17-inch Alpina wheels, typically fitted with 235/40R17 front and 265/35R17 rear tires, providing good grip and handling balance.
Market Reception & Comparison
The Alpina B3 Cabrio was generally well-received by automotive critics. It was praised for its blend of performance, luxury, and refinement. Reviewers noted the smooth power delivery of the engine, the comfortable ride, and the high-quality interior. Compared to the standard E36 Cabriolet, the B3 offered a significant performance upgrade and a more exclusive driving experience. Compared to the M3 Cabriolet, the B3 was seen as a more relaxed and comfortable grand tourer, sacrificing some of the M3’s raw performance for added refinement. Fuel economy was reasonable for a high-performance convertible, averaging around 24.2 mpg in combined driving. Reliability was generally good, although the SwitchTronic transmission could require more maintenance than a manual gearbox.
Legacy
Today, the Alpina B3 Cabrio (E36) 3.0i 24V is a sought-after classic among enthusiasts. Its limited production numbers and unique character make it a collectible vehicle. The M30 engine is known for its durability and relatively straightforward maintenance. The SwitchTronic transmission, while potentially requiring more attention than a manual, is generally reliable if properly maintained. Well-maintained examples command a premium in the used car market, appealing to collectors and drivers who appreciate the blend of performance, luxury, and exclusivity that Alpina offered in the 1990s. The B3 Cabrio represents a high point in Alpina’s history, showcasing their ability to create unique and desirable automobiles based on BMW platforms.
