The Citroën CX 2400, specifically the variant equipped with the 2.4-liter engine producing 116 horsepower and the Cmatic automatic transmission, represents a fascinating intersection of innovative engineering and comfortable touring in the late 1970s. Produced between 1976 and 1980, this model occupied a mid-range position within the CX lineup, offering a more accessible entry point to the technologically advanced CX platform compared to the higher-performance versions. It was a key offering in Citroën’s domestic European market, appealing to buyers seeking a sophisticated and uniquely styled vehicle.
Technical Specifications
| Brand | Citroën |
| Model | CX |
| Generation | CX I |
| Type (Engine) | 2400 (116 Hp) Cmatic |
| Start of production | 1976 |
| 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 | 13.4 sec |
| Acceleration 0 – 62 mph | 13.4 sec |
| Acceleration 0 – 60 mph | 12.7 sec |
| Maximum speed | 177 km/h (109.98 mph) |
| Weight-to-power ratio | 11.5 kg/Hp, 87.2 Hp/tonne |
| Weight-to-torque ratio | 7.4 kg/Nm, 135.3 Nm/tonne |
| Power | 116 Hp @ 5500 rpm |
| Power per litre | 49.4 Hp/l |
| Torque | 180 Nm @ 2750 rpm (132.76 lb.-ft. @ 2750 rpm) |
| Engine layout | Front, Transverse |
| Engine Model/Code | M23.623 |
| 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 | 8.75:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Carburettor |
| Engine aspiration | Naturally aspirated |
| 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 | 1330 kg (2932.15 lbs) |
| Max. weight | 1790 kg (3946.27 lbs) |
| Max load | 460 kg (1014.13 lbs) |
| Trunk (boot) space – minimum | 325 l (11.48 cu. ft.) |
| Fuel tank capacity | 68 l (17.96 US gal | 14.96 UK gal) |
| Permitted trailer load without brakes | 650 kg (1433 lbs) |
| Length | 4659 mm (183.43 in.) |
| Width | 1734 mm (68.27 in.) |
| Height | 1360 mm (53.54 in.) |
| Wheelbase | 2845 mm (112.01 in.) |
| Front track | 1474 mm (58.03 in.) |
| Rear (Back) track | 1360 mm (53.54 in.) |
| Front overhang | 1050 mm (41.34 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. |
| Drive wheel | Front wheel drive |
| Number of gears and type of gearbox | 3 gears, automatic transmission |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Steering type | Steering rack and pinion |
| Wheel rims size | 5.5J x 14 |
INTRODUCTION
The Citroën CX, launched in 1974, was a radical departure from conventional automotive design. It represented Citroën’s continued commitment to innovation, building upon the legacy of the DS and ID models. The CX I 2400 Cmatic, introduced a few years into the CX’s production run, offered a blend of the car’s advanced features with a more accessible engine and the convenience of an automatic transmission. This variant aimed to broaden the CX’s appeal, attracting buyers who desired a comfortable and technologically sophisticated vehicle without the expense or complexity of the top-tier models. It was positioned as a comfortable cruiser, ideal for long-distance journeys.
Powertrain & Engine Architecture
The heart of the CX 2400 Cmatic is the M23.623 inline-four cylinder engine, displacing 2.4 liters. This engine, while not the most powerful in the CX range, was known for its smoothness and relative reliability. It utilized a single overhead camshaft and two valves per cylinder. Fuel delivery was managed by a Solex C35 PHH carburetor, a common setup for European vehicles of the era. The engine produced 116 horsepower at 5500 rpm and 180 Nm (132.76 lb.-ft.) of torque at 2750 rpm. The ‘Cmatic’ transmission was Citroën’s proprietary three-speed automatic gearbox. Unlike conventional automatics, the Cmatic system employed a torque converter and planetary gearsets, but also incorporated a hydraulic control system linked to the car’s high-pressure hydraulic suspension. This integration allowed for smooth and relatively quick shifts, although it wasn’t known for its sportiness.
Driving Characteristics
The CX 2400 Cmatic offered a distinctly different driving experience compared to its manual transmission counterparts or the more powerful versions like the CX 2500 or Prestige. The automatic transmission, while convenient, did diminish the car’s overall performance. Acceleration from 0-60 mph took around 12.7 seconds, and top speed was approximately 109.98 mph. The three-speed gearbox meant that the engine often felt strained during rapid acceleration, and the lack of a fourth gear resulted in higher engine speeds at highway cruising speeds. However, the CX’s legendary hydropneumatic suspension provided an exceptionally comfortable ride, absorbing bumps and imperfections in the road with ease. The steering, also hydraulically assisted, was light and precise, making the car easy to maneuver despite its size.
Equipment & Trim Levels
The CX I 2400 Cmatic came reasonably well-equipped for its time. Standard features included comfortable cloth upholstery, a comprehensive instrument panel, and power-assisted steering. The interior design was typically Citroën – functional, ergonomic, and somewhat unconventional. Optional extras included leather upholstery, air conditioning, a sunroof, and upgraded audio systems. The trim level was generally considered to be mid-range, offering a good balance of comfort and features without the luxury appointments of the higher-spec models.
Chassis & Braking
The CX’s chassis was a monocoque construction, providing a strong and rigid platform. The defining feature of the CX was its hydropneumatic suspension system, developed by Citroën. This system used self-leveling spheres filled with nitrogen and hydraulic fluid to provide a remarkably smooth and controlled ride. The front suspension utilized double wishbones, while the rear employed trailing arms. Braking was handled by ventilated discs at the front and solid discs at the rear, providing adequate stopping power for the car’s weight and performance. The steering system was a rack and pinion setup with hydraulic assistance.
Market Reception & Comparison
The CX 2400 Cmatic was generally well-received by automotive critics, who praised its comfortable ride, innovative technology, and distinctive styling. However, some criticized the performance of the automatic transmission and the relatively high price compared to conventional cars. Compared to the manual transmission versions of the CX 2400, the Cmatic offered less engaging driving experience but greater convenience. The higher-output CX 2500 and Prestige models provided significantly more performance, but at a higher cost. The CX 2400 Cmatic appealed to buyers who prioritized comfort and ease of use over outright speed.
Legacy
The Citroën CX, while not a massive sales success, remains a highly regarded and collectible classic car. The 2400 Cmatic variant, while not the most sought-after version, offers a unique combination of features and represents a significant piece of automotive history. The M23 engine, when properly maintained, proved to be relatively reliable, although the Cmatic transmission can be prone to issues if not serviced regularly. Today, well-maintained examples of the CX 2400 Cmatic are increasingly sought after by enthusiasts who appreciate its innovative engineering, comfortable ride, and distinctive styling. Its hydropneumatic suspension, while requiring specialized knowledge for maintenance, continues to impress with its ability to deliver a uniquely smooth and refined driving experience.
