Technical Specifications For The 1990 Nissan 240sx Coupe
The 1990 Nissan 240SX coupe, part of the S13 generation, holds a special place in automotive history. Revered for its balanced chassis, affordability, and inherent tuning potential, it became a darling of the drifting and sports compact scenes. But beyond the sideways action and engine swaps, the 240SX boasted a cleverly engineered design. This technical guide delves into the specifications that made the '90 240SX coupe a standout performer.
Chassis and Body
The S13 platform employed a unibody construction, providing a solid foundation for the vehicle. Its dimensions contribute significantly to its handling characteristics. The coupe features a wheelbase of approximately 97.4 inches (2474 mm), a length of 176.2 inches (4475 mm), a width of 66.5 inches (1689 mm), and a height of around 50.6 inches (1285 mm), although these figures can vary slightly depending on specific trims and options. This relatively short wheelbase contributed to its nimble and responsive handling.
Suspension System
One of the defining features of the 240SX was its independent suspension system. Both front and rear suspensions utilized struts, coil springs, and anti-roll bars. The front suspension incorporated MacPherson struts, known for their simplicity and cost-effectiveness, while offering decent performance. The rear employed a multi-link independent suspension. This setup, more complex than the front, allowed for greater control over wheel camber and toe angles during suspension travel, contributing significantly to its handling prowess. This independent rear suspension was a key factor in its popularity among enthusiasts. The spring rates and damper settings were tuned to provide a balance between comfort and sporty handling. While considered adequate for the time, many owners opted for aftermarket springs and dampers to further tailor the suspension to their specific needs, whether it be for track days, drifting, or simply improved street performance.
Steering
The 240SX used a power-assisted rack-and-pinion steering system. This system provides a direct and responsive feel, crucial for driver feedback. The steering ratio, while not overly aggressive, provided a good balance between quickness and stability. The power steering pump, driven by the engine via a belt, provided assistance to reduce steering effort, particularly at low speeds. The steering column featured a collapsible design, intended to reduce the risk of injury in the event of a collision.
Brakes
The braking system of the 1990 240SX typically consisted of disc brakes at both the front and rear. The front discs were ventilated, which improved their ability to dissipate heat under hard braking, reducing the risk of brake fade. The rear discs were solid. The system incorporated a tandem master cylinder and a vacuum booster to amplify the driver's pedal input. ABS (Anti-lock Braking System) was an available option on some models, enhancing braking performance, particularly in slippery conditions. The brake calipers were typically single-piston designs, though aftermarket upgrades often involved multi-piston calipers for increased stopping power and improved brake feel. The brake lines were usually made of rubber, but stainless steel braided lines became a popular upgrade for improved brake feel and resistance to expansion under pressure.
Engine and Drivetrain
The 1990 240SX was primarily powered by the KA24E engine, a 2.4-liter, single overhead cam (SOHC), four-cylinder engine. This engine was known for its reliability and decent torque output. While not as powerful as later engine swaps enthusiasts would perform, it provided adequate performance for daily driving and spirited runs.
KA24E Engine Specifications
- Displacement: 2.4 liters (2389 cc)
- Configuration: Inline-4
- Valvetrain: SOHC, 12 valves (3 valves per cylinder: 2 intake, 1 exhaust)
- Bore x Stroke: 89 mm x 96 mm
- Compression Ratio: 9.5:1
- Fuel Delivery: Electronic Fuel Injection (EFI)
- Maximum Power: Approximately 140 horsepower at 5600 rpm
- Maximum Torque: Approximately 152 lb-ft at 4400 rpm
The KA24E engine featured a cast iron block and an aluminum cylinder head. The single overhead cam was driven by a timing chain. Fuel injection was handled by a multi-point EFI system, ensuring precise fuel delivery and efficient combustion. The engine was designed to run on regular unleaded gasoline.
Transmission
The 1990 240SX was available with either a 5-speed manual transmission or a 4-speed automatic transmission. The 5-speed manual, manufactured by Aisin, was the preferred choice for enthusiasts due to its greater control and more engaging driving experience. The gear ratios were chosen to provide a balance between acceleration and fuel economy. The automatic transmission offered convenience, but it sacrificed some of the performance potential of the car. The clutch in the manual transmission was a single-disc design. Over time, many owners upgraded to heavier-duty clutches to handle increased power from engine modifications.
Differential
The 240SX came standard with an open differential. This type of differential allows the wheels to spin at different speeds, which is necessary for turning. However, it also means that if one wheel loses traction, all of the power will be sent to that wheel, leaving the other wheel with no power. This can be a problem in situations where traction is limited, such as on slippery surfaces or during aggressive cornering. Consequently, the open differential became one of the most common targets for upgrades. Many owners installed limited-slip differentials (LSDs) to improve traction and handling. An LSD distributes power more evenly between the wheels, even when one wheel loses traction.
Electrical System
The 1990 240SX utilized a 12-volt electrical system. The battery was typically located in the engine bay. The alternator, driven by a belt from the engine, provided power to recharge the battery and run the electrical components of the car. The car featured a fuse box, containing fuses to protect the electrical circuits from overloads. The headlights were halogen bulbs, and the taillights were incandescent bulbs. The instrument cluster included gauges for speed, RPM, fuel level, and coolant temperature.
Interior
The interior of the 1990 240SX was functional and relatively spartan, typical of sports coupes of the era. The seats were cloth upholstered and offered decent support. The dashboard was made of plastic and featured a simple, straightforward design. The car came standard with air conditioning, power windows, and power door locks. The sound system typically consisted of an AM/FM radio and cassette player. The interior design prioritized functionality over luxury, with a focus on providing a comfortable and engaging driving experience. Many owners customized their interiors with aftermarket seats, steering wheels, and shift knobs to personalize their cars.
Performance
The performance of the 1990 Nissan 240SX coupe was respectable for its time, but its true potential lay in its tunability and balance. The KA24E engine provided adequate power for daily driving, and the chassis offered excellent handling characteristics. The car's relatively light weight also contributed to its agility.
Approximate Performance Figures:
- 0-60 mph: Approximately 8.5-9.0 seconds
- Top Speed: Approximately 125-130 mph
These figures could vary depending on the specific car and its condition.
Conclusion
The 1990 Nissan 240SX coupe was a well-engineered vehicle that offered a compelling combination of performance, affordability, and reliability. Its balanced chassis, independent suspension, and responsive steering made it a joy to drive. While the KA24E engine was not the most powerful, it was dependable and provided a solid foundation for future upgrades. The 240SX's enduring popularity is a testament to its inherent design strengths and its ability to be easily modified and customized to suit the individual needs of its owners. Its technical specifications reveal a thoughtfully designed car that was more than just a pretty face – it was a capable and rewarding machine that continues to captivate enthusiasts to this day.