The Citroën CX I Prestige 2400 Injection, produced between 1977 and 1980, represents a high-water mark in Citroën’s long history of innovative automotive engineering. Positioned as a premium variant within the first generation (Series I) of the CX model range, the 2400 Injection offered a blend of luxury, performance, and the advanced hydropneumatic suspension system for which Citroën was renowned. It served as a flagship model, showcasing the technological prowess of the French manufacturer and competing with vehicles like the Peugeot 604 and Rover SD1 in the executive car segment. The CX, internally designated as the G series, succeeded the iconic Citroën DS, inheriting and refining many of its predecessor’s groundbreaking features.
Technical Specifications
| Brand | Citroen |
| Model | CX |
| Generation | CX I |
| Type (Engine) | Prestige 2400 (128 Hp) Injection |
| Start of production | 1977 |
| End of production | 1980 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Hatchback |
| Seats | 5 |
| Doors | 5 |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 11.1 sec |
| Acceleration 0 – 62 mph | 11.1 sec |
| Acceleration 0 – 60 mph | 10.5 sec |
| Maximum speed | 190 km/h (118.06 mph) |
| Weight-to-power ratio | 11.5 kg/Hp, 86.8 Hp/tonne |
| Weight-to-torque ratio | 7.5 kg/Nm, 133.6 Nm/tonne |
| Power | 128 Hp @ 4800 rpm |
| Power per litre | 54.5 Hp/l |
| Torque | 197 Nm @ 3600 rpm (145.3 lb.-ft. @ 3600 rpm) |
| Engine layout | Front, Transverse |
| Engine Model/Code | M23.622 |
| Engine displacement | 2347 cm3 (143.22 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 93.5 mm (3.68 in.) |
| Piston Stroke | 85.5 mm (3.37 in.) |
| Compression ratio | 9:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Engine oil capacity | 5.3 l (5.6 US qt | 4.66 UK qt) |
| Coolant | 11 l (11.62 US qt | 9.68 UK qt) |
| Kerb Weight | 1475 kg (3251.82 lbs) |
| Max. weight | 1925 kg (4243.9 lbs) |
| Max load | 450 kg (992.08 lbs) |
| Trunk (boot) space – minimum | 325 l (11.48 cu. ft.) |
| Fuel tank capacity | 68 l (17.96 US gal | 14.96 UK gal) |
| Length | 4916 mm (193.54 in.) |
| Width | 1734 mm (68.27 in.) |
| Height | 1357 mm (53.43 in.) |
| Wheelbase | 3095 mm (121.85 in.) |
| Front track | 1474 mm (58.03 in.) |
| Rear (Back) track | 1360 mm (53.54 in.) |
| Front overhang | 1057 mm (41.61 in.) |
| Rear overhang | 764 mm (30.08 in.) |
| Ride height (ground clearance) | 155 mm (6.1 in.) |
| Drag coefficient (Cd) | 0.37 |
| Minimum turning circle | 11.80 m (38.71 ft.) |
| 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 | 5 gears, manual transmission |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Steering type | Steering rack and pinion |
| Wheel rims size | 5.5J x 14 |
Powertrain & Engine Architecture
The Citroën CX I Prestige 2400 Injection was powered by the M23.622 engine, a 2.4-liter inline-four cylinder gasoline engine. This engine was a development of the earlier M23 series, featuring a cast iron block and an aluminum cylinder head. The key feature distinguishing this variant was its Bosch multi-port fuel injection system, replacing the carburetor found on lower-spec CX models. This injection system significantly improved throttle response, fuel efficiency, and overall engine refinement. The engine produced 128 horsepower at 4800 rpm and 197 Nm (145.3 lb-ft) of torque at 3600 rpm. The engine utilized a two-valve per cylinder configuration and a compression ratio of 9:1. The engine was transversely mounted, driving the front wheels through a five-speed manual transmission. This layout contributed to the CX’s excellent handling characteristics and interior space utilization.
Driving Characteristics
The CX I Prestige 2400 Injection offered a unique driving experience largely defined by its hydropneumatic suspension. This system, carried over from the DS, provided an exceptionally smooth and comfortable ride, absorbing bumps and imperfections in the road with remarkable ease. The 128 hp engine, while not overtly powerful, provided adequate performance for comfortable cruising and overtaking. Acceleration from 0 to 60 mph took approximately 10.5 seconds, and the car had a top speed of around 118 mph. Compared to the later 2.5-liter engines, the 2400 felt less stressed at higher speeds, but also lacked the outright punch of the larger displacement units. The five-speed manual transmission allowed for precise control over the engine’s power band, although the gear ratios were relatively long, prioritizing fuel economy and relaxed cruising over rapid acceleration. The steering, also hydraulically assisted, was light and precise, contributing to the car’s effortless driving feel.
Equipment & Trim Levels
The “Prestige” designation indicated a high level of equipment. Standard features included comfortable cloth upholstery, a wood-rimmed steering wheel, central locking, electric windows, and a high-quality radio. The interior was designed with a focus on ergonomics and comfort, featuring supportive seats and a well-laid-out dashboard. Optional extras included leather upholstery, air conditioning, and a sunroof. The CX I Prestige 2400 Injection was positioned as a luxurious and well-equipped vehicle, appealing to buyers who prioritized comfort and refinement over outright performance.
Chassis & Braking
The CX featured a monocoque chassis construction, providing a strong and rigid platform. The hydropneumatic suspension system, utilizing self-leveling spheres and hydraulic dampers, was the cornerstone of the car’s handling and ride quality. The front suspension utilized independent double wishbones, while the rear suspension employed trailing arms. Braking was provided by ventilated discs at the front and solid discs at the rear, offering good stopping power. The steering system was a rack and pinion type with hydraulic assistance, providing precise and effortless steering control.
Market Reception & Comparison
The Citroën CX I Prestige 2400 Injection was generally well-received by automotive critics, who praised its innovative suspension system, comfortable ride, and refined engine. However, some critics noted that the car’s styling was somewhat polarizing, and its complex hydropneumatic system could be expensive to maintain. Compared to other trims in the CX lineup, the 2400 Injection offered a better balance of performance and refinement than the lower-powered 2.0-liter models, but lacked the outright performance of the later 2.5-liter and turbocharged variants. Fuel economy was reasonable for the time, averaging around 22-25 mpg.
Legacy
The Citroën CX I Prestige 2400 Injection remains a highly regarded classic car, celebrated for its innovative engineering and distinctive styling. While the hydropneumatic suspension system requires specialized maintenance, the M23.622 engine is generally considered to be reliable and durable. Today, well-maintained examples of the CX I Prestige 2400 Injection are sought after by collectors and enthusiasts, representing a unique and rewarding driving experience. The car’s legacy lies in its pioneering use of technology and its commitment to providing an exceptionally comfortable and refined ride.
