The BMW 628CSi automatic, produced from 1982 to 1987, represents a refined iteration of the E24 6 Series coupe. Positioned as a mid-range offering within the 6 Series lineup, it bridged the gap between the entry-level 626CSi and the high-performance 635CSi. This variant aimed to deliver a balance of luxury, comfort, and respectable performance, appealing to buyers who prioritized a smooth driving experience over outright speed. The 628CSi, particularly with the automatic transmission, became a popular choice for grand touring, offering a sophisticated alternative to sportier coupes.
Technical Specifications
| Brand | BMW |
| Model | 6 Series |
| Generation | 6 Series (E24, facelift 1982) |
| Type (Engine) | 628CSi (184 Hp) Automatic |
| Start of production | 1982 |
| End of production | 1987 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 14.4 l/100 km (16.3 US mpg, 19.6 UK mpg, 6.9 km/l) |
| Fuel consumption (extra urban) | 6.8 l/100 km (34.6 US mpg, 41.5 UK mpg, 14.7 km/l) |
| Fuel consumption (combined) | 10 l/100 km (23.5 US mpg, 28.2 UK mpg, 10 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 10.9 sec |
| Acceleration 0 – 62 mph | 10.9 sec |
| Acceleration 0 – 60 mph | 10.4 sec |
| Maximum speed | 204 km/h (126.76 mph) |
| Weight-to-power ratio | 7.8 kg/Hp, 128.7 Hp/tonne |
| Weight-to-torque ratio | 6 kg/Nm, 167.8 Nm/tonne |
| Power | 184 Hp @ 5800 rpm |
| Power per litre | 66 Hp/l |
| Torque | 240 Nm @ 4200 rpm (177.01 lb.-ft. @ 4200 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M30 |
| Engine displacement | 2788 cm3 (170.13 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 86 mm (3.39 in.) |
| Piston Stroke | 80 mm (3.15 in.) |
| Compression ratio | 9.3:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Engine oil capacity | 5.8 l (6.13 US qt | 5.1 UK qt) |
| Coolant | 12 l (12.68 US qt | 10.56 UK qt) |
| Kerb Weight | 1430 kg (3152.61 lbs.) |
| Max. weight | 1850 kg (4078.55 lbs.) |
| Max load | 420 kg (925.94 lbs.) |
| Trunk (boot) space – minimum | 415 l (14.66 cu. ft.) |
| Fuel tank capacity | 70 l (18.49 US gal | 15.4 UK gal) |
| Length | 4755 mm (187.2 in.) |
| Width | 1725 mm (67.91 in.) |
| Height | 1365 mm (53.74 in.) |
| Wheelbase | 2625 mm (103.35 in.) |
| Front track | 1430 mm (56.3 in.) |
| Rear (Back) track | 1460 mm (57.48 in.) |
| Drag coefficient (Cd) | 0.41 |
| Minimum turning circle | 11.2 m (36.75 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Drive wheel | Rear wheel drive |
| Number of gears | 4 gears, automatic transmission |
| Front suspension | Independent, type McPherson with coil spring and anti-roll bar |
| Rear suspension | Independent coil spring |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Tires size | 205/70 VR14 |
| Wheel rims size | 14 |
Powertrain & Engine Architecture
The heart of the 628CSi is the M30 inline-six engine, specifically the 2.8-liter variant. This engine, a cornerstone of BMW’s engineering prowess during the 1980s, featured a cast-iron block and an aluminum cylinder head. The 628CSi utilized Bosch Motronic fuel injection, a sophisticated system for its time, which optimized fuel delivery and ignition timing for improved efficiency and performance. The engine produced 184 horsepower at 5800 rpm and 240 Nm (177 lb-ft) of torque at 4200 rpm. The automatic transmission was a four-speed unit, designed to provide smooth and effortless gear changes. While not as sporty as the available five-speed manual, it complemented the 628CSi’s grand touring character.
Driving Characteristics
The 628CSi automatic offered a distinctly different driving experience compared to its manual counterpart or the more powerful 635CSi. The automatic transmission, while providing convenience, resulted in slightly slower acceleration – 0 to 60 mph in approximately 10.4 seconds. The gear ratios were tuned for comfortable cruising, prioritizing relaxed highway driving over aggressive acceleration. The engine delivered smooth, linear power, making it easy to modulate throttle response. Compared to the 635CSi, the 628CSi felt less urgent, but it still provided ample power for overtaking and maintaining comfortable speeds. The automatic transmission did diminish some of the driver engagement, but the overall experience remained refined and enjoyable.
Equipment & Trim Levels
The 628CSi automatic came reasonably well-equipped as standard. Interior features typically included cloth upholstery, power windows, central locking, and a basic sound system. Leather upholstery, a sunroof, and upgraded audio systems were popular optional extras. The dashboard layout was typical of BMWs of the era, with a driver-focused design and clear instrumentation. The 628CSi often sat in a middle ground, offering more luxury features than the base 626CSi but lacking some of the performance-oriented options found on the 635CSi, such as sport suspension or limited-slip differentials.
Chassis & Braking
The E24 6 Series featured an independent suspension system all around, with McPherson struts at the front and semi-trailing arms at the rear. The 628CSi utilized a coil spring setup, providing a comfortable ride. Braking duties were handled by ventilated discs at the front and solid discs at the rear. An Anti-lock Braking System (ABS) was standard, enhancing safety and stability, particularly in adverse conditions. The chassis was designed to balance handling and comfort, offering a stable and predictable driving experience. The 628CSi’s weight of around 1430 kg (3153 lbs) was relatively moderate, contributing to its manageable handling characteristics.
Market Reception & Comparison
The 628CSi automatic was generally well-received by automotive critics. It was praised for its comfortable ride, refined engine, and luxurious interior. However, some reviewers noted that the automatic transmission diminished the sporty character of the 6 Series. Compared to the 635CSi, the 628CSi offered a more affordable entry point into the 6 Series range, while still providing a high level of sophistication. Fuel economy was reasonable for a vehicle of its size and performance, averaging around 23.5 US mpg combined. Reliability was generally good, although maintenance costs could be significant due to the complexity of the M30 engine and the BMW’s overall engineering.
Legacy
The BMW 628CSi automatic has become a sought-after classic among BMW enthusiasts. The M30 engine is known for its durability and relatively straightforward maintenance, although age-related issues are common. Well-maintained examples command respectable prices in the used car market. The 628CSi represents a sweet spot in the E24 lineup, offering a blend of performance, luxury, and reliability that appeals to collectors and drivers alike. Its enduring appeal lies in its timeless design, comfortable driving experience, and the prestige associated with the BMW brand.
