Comprehensive Technical Specifications For All Nissan 240sx Model Years

The Nissan 240SX, a darling of the drift and tuner communities, holds a special place in automotive history. Its rear-wheel-drive configuration, relatively light weight, and responsive engine made it a blank canvas for modification and performance enhancement. This comprehensive guide delves into the technical specifications of all 240SX model years, offering an analytical look at the mechanical and electrical systems that defined this iconic car.

First Generation (S13: 1989-1994)

The S13 chassis marked the beginning of the 240SX lineage, offering both coupe (fastback) and hatchback (liftback) body styles. While aesthetically different, the underlying mechanicals remained largely consistent across both variants.

Engine Specifications:

The initial S13 models (1989-1990) were powered by the KA24E engine, a 2.4-liter single overhead cam (SOHC) inline-four. Here's a breakdown:

• Engine Code: KA24E
• Displacement: 2389 cc (145.8 cu in)
• Bore x Stroke: 89.0 mm x 96.0 mm (3.50 in x 3.78 in)
• Compression Ratio: 8.6:1
• Fuel System: Electronic Fuel Injection (EFI)
• Power Output: 140 hp (104 kW) @ 5600 rpm
• Torque Output: 152 lb⋅ft (206 N⋅m) @ 4400 rpm

From 1991 to 1994, the 240SX received an updated engine, the KA24DE, featuring dual overhead cams (DOHC) and increased power:

• Engine Code: KA24DE
• Displacement: 2389 cc (145.8 cu in)
• Bore x Stroke: 89.0 mm x 96.0 mm (3.50 in x 3.78 in)
• Compression Ratio: 9.5:1
• Fuel System: Electronic Fuel Injection (EFI)
• Power Output: 155 hp (116 kW) @ 5600 rpm
• Torque Output: 160 lb⋅ft (217 N⋅m) @ 4400 rpm

The increased power of the KA24DE stemmed from improved cylinder head design, allowing for better airflow and higher revving capabilities. However, both KA engines are known for their robust bottom-end torque, making them suitable for drifting and spirited driving.

Transmission Specifications:

The S13 240SX was available with two transmission options:

• 5-Speed Manual: This was the more desirable option for enthusiasts, offering greater control and engagement. Specific gear ratios varied slightly depending on the year and trim level. Typically, it was the FS5W71C transmission.
• 4-Speed Automatic: This provided a more relaxed driving experience, but lacked the responsiveness of the manual.

The manual transmission is known for its relatively short throw and ease of use. Many owners later upgrade the clutch and flywheel for improved performance and durability, especially when increasing engine power.

Suspension and Brakes:

The S13 utilized a fully independent suspension system:

• Front: MacPherson struts with coil springs and stabilizer bar
• Rear: Multi-link suspension with coil springs and stabilizer bar

This setup provided a good balance of handling and ride comfort. The multi-link rear suspension is particularly noteworthy, as it allowed for relatively complex adjustments to camber and toe, making it a popular choice for drifting and track use.

• Brakes: Disc brakes were standard on all four wheels, providing adequate stopping power. ABS (Anti-lock Braking System) was available as an option.

Electrical System:

The S13 operates on a 12-volt electrical system. The engine management system (EMS) varied depending on the engine. The KA24E used a simpler system than the KA24DE. Wiring diagrams are crucial for troubleshooting and modification.

Second Generation (S14: 1995-1998)

The S14 generation brought a revised styling and slight improvements in performance. While still powered by the KA24DE, minor refinements were made.

Engine Specifications:

The S14 continued to use the KA24DE engine. Though the fundamental specifications remained the same as the later S13 models (1991-1994), some subtle tuning differences may have existed. These differences, if any, were minor and resulted in negligible performance changes. Nissan focused on improving refinement and aesthetics rather than significantly altering the engine's output.

Transmission Specifications:

• 5-Speed Manual: Similar to the S13, the FS5W71C transmission was used. Gear ratios may have been slightly adjusted.
• 4-Speed Automatic: Continued as an option.

Suspension and Brakes:

The S14 retained the same suspension layout as the S13:

• Front: MacPherson struts with coil springs and stabilizer bar
• Rear: Multi-link suspension with coil springs and stabilizer bar

However, the S14 often featured slightly stiffer springs and dampers, resulting in improved handling at the expense of some ride comfort. Brake specifications remained largely unchanged, with disc brakes on all four wheels and optional ABS.

Electrical System:

The S14's electrical system was updated compared to the S13. The ECU (Engine Control Unit) was refined, providing more precise control over fuel and ignition. Additionally, the S14 incorporated more advanced diagnostic features.

Key Differences and Considerations:

• Engine: The transition from KA24E to KA24DE in the S13 is the most significant engine-related difference. The KA24DE offered noticeable performance gains.
• Styling: The S13 and S14 feature drastically different styling, with the S14 being larger and more curvaceous.
• Weight: The S14 is slightly heavier than the S13, which can impact handling and acceleration.
• Availability: Both generations are becoming increasingly rare and sought after, especially in good condition.
• Aftermarket Support: A vast aftermarket exists for both S13 and S14 240SX models, offering a wide range of performance and cosmetic upgrades.
• Rust: Both generations are prone to rust, especially in areas with harsh winter climates. Thorough inspection is crucial before purchasing.

Common Modifications and Upgrades:

The 240SX is a highly modifiable platform. Common upgrades include:

• Engine Swaps: The SR20DET (a 2.0-liter turbocharged engine) is a popular swap, offering significantly more power than the KA engines. Other swaps include the RB25DET and 1JZ-GTE.
• Turbocharging: Turbocharging the KA24DE is another way to increase power, though it requires careful tuning and supporting modifications.
• Suspension Upgrades: Coilovers, sway bars, and adjustable control arms are common suspension upgrades for improved handling.
• Brake Upgrades: Upgraded brake rotors, calipers, and pads can improve stopping power, especially with increased engine power.
• ECU Tuning: Standalone engine management systems allow for precise control over fuel, ignition, and other engine parameters.

Conclusion:

The Nissan 240SX, in both S13 and S14 guises, remains a compelling platform for automotive enthusiasts. Its rear-wheel-drive layout, independent suspension, and relatively simple mechanicals make it a rewarding car to drive and modify. Understanding the technical specifications of each model year is essential for making informed decisions regarding maintenance, upgrades, and overall ownership. While the KA24DE engine is not the most powerful, its reliability and potential for modification, combined with the balanced chassis, solidify the 240SX's place as a true icon of the tuner era. Proper care and maintenance are crucial to preserving these increasingly rare and valuable vehicles.