Technical Specifications For The 1997 Nissan 240sx (s14 Kouki)

Alright folks, let's dive deep into the technical specifications of the 1997 Nissan 240SX, specifically the Kouki model (S14 chassis). This is the last year of the legendary 240SX in the US market, and it remains a popular choice for enthusiasts and modders due to its rear-wheel drive layout, robust engine, and relatively simple mechanics. We'll break down everything from the engine and drivetrain to the suspension and electrical systems. Consider this your detailed tech sheet, perfect for planning your next upgrade or troubleshooting a gremlin.

Engine (KA24DE)

The heart of the '97 240SX is the KA24DE engine, a 2.4-liter inline-four cylinder. While not the fire-breathing SR20DET found in Japanese models, it's a reliable and torquey powerplant. Let's look at the specifics:

Displacement: 2389 cc (145.8 cu in)
Engine Type: Water-cooled, inline 4-cylinder, DOHC (Double Overhead Camshaft)
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) - Nissan ECCS (Electronically Concentrated Control System)
Horsepower: 155 hp (116 kW) @ 5600 rpm
Torque: 160 lb-ft (217 Nm) @ 4400 rpm
Firing Order: 1-3-4-2

Understanding the KA24DE: The DOHC configuration means it uses two camshafts in the cylinder head, one for intake valves and one for exhaust valves. This allows for better valve control and, consequently, improved engine breathing compared to a single overhead cam (SOHC) design. The ECCS is Nissan's early engine management system, controlling fuel injection, ignition timing, and idle speed. While relatively simple by modern standards, it's effective and relatively easy to diagnose with the right tools.

Common KA24DE Issues: These engines are generally reliable, but some common issues include timing chain wear (resulting in a rattling noise), distributor problems, and oil leaks (particularly around the valve cover and rear main seal). Regular maintenance, including oil changes and timing chain replacement at recommended intervals, is crucial for longevity.

Drivetrain

The 240SX is, of course, a rear-wheel drive car. Let's examine the components involved:

Transmission: Available in either a 5-speed manual (FS5W71C) or a 4-speed automatic.
Differential: Open differential standard. Aftermarket limited-slip differentials (LSDs) are a popular upgrade.
Final Drive Ratio: Varies depending on the transmission and trim level, but typically around 4.083:1 for manual transmissions and slightly higher for automatics.

Transmissions: The FS5W71C manual transmission is known for its durability, making it a popular choice for those who plan to drift or race their 240SX. The automatic transmission, while less engaging, is also reasonably robust. Shifting feel on the manual can be improved with short-throw shifters, which are readily available in the aftermarket.

Differentials: The factory open differential transfers power to the wheel with the least amount of traction, which is undesirable for performance driving. Installing an LSD, such as a clutch-type, Torsen, or viscous LSD, significantly improves traction and allows for controlled drifts.

Suspension and Brakes

The 240SX's suspension setup contributes significantly to its handling prowess:

Front Suspension: Independent strut type with coil springs and stabilizer bar.
Rear Suspension: Independent multi-link type with coil springs and stabilizer bar.
Brakes: Front: Ventilated discs. Rear: Solid discs. ABS was an option.
Steering: Rack and pinion, power assisted.

Suspension Details: The independent suspension provides good handling characteristics and a relatively comfortable ride. The multi-link rear suspension helps to maintain consistent camber and toe angles during suspension travel, improving grip. Common suspension upgrades include lowering springs, coilovers (adjustable ride height and damping), sway bars, and aftermarket control arms to adjust camber and caster angles.

Braking System: The disc brakes offer adequate stopping power for street use. Upgrading to larger rotors, calipers, and performance brake pads is recommended for track use or spirited driving. ABS (Anti-lock Braking System) was an option, but many enthusiasts prefer to disable it for track use to have more direct control over braking.

Electrical System

Let's look at the electrical components:

Battery: 12V, typically Group Size 35
Alternator: Typically rated around 80-90 amps.
Ignition System: Distributor-based ignition system controlled by the ECCS.
ECU: Nissan ECCS (Electronically Concentrated Control System)

Electrical Notes: The electrical system is generally reliable, but issues can arise from corrosion, damaged wiring, and failing sensors. The ECU is responsible for controlling various engine functions, and aftermarket ECUs are often used for modified engines to optimize performance and tune for different modifications. A common issue on older 240SX models is wiring harness degradation due to age and heat. Inspecting and repairing the wiring harness is important for maintaining reliability.

Chassis and Body

The S14 chassis is a strong and relatively lightweight platform.

Chassis Code: S14
Curb Weight: Approximately 2700-2800 lbs (depending on options and trim level).
Wheelbase: 99.4 inches
Overall Length: 178.0 inches
Overall Width: 68.5 inches
Overall Height: 52.0 inches

Body Notes: The Kouki (後期) refers to the later version of the S14 chassis, produced from 1997-1998 (in Japan). It's distinguished by its updated front and rear styling, including different headlights, taillights, and bumpers. The body is prone to rust, particularly in areas exposed to moisture and road salt. Checking for rust is essential before purchasing a 240SX. Aftermarket body kits and aero parts are readily available for those who want to customize the appearance of their car.

Important Considerations for Modding

Before you start modifying your 240SX, it's essential to consider a few things:

Budget: Modifying a car can be expensive. Set a realistic budget and stick to it.
Reliability: Modifications can sometimes compromise reliability. Choose parts carefully and ensure they are installed correctly.
Local Laws: Be aware of local laws and regulations regarding vehicle modifications.
Maintenance: Modified cars often require more frequent maintenance. Be prepared to spend more time and money on upkeep.

Common Mods: Some popular modifications for the 240SX include engine swaps (SR20DET, LSx), turbocharging, suspension upgrades, brake upgrades, and aftermarket ECUs. Research thoroughly before undertaking any modifications and consult with experienced mechanics or tuners if you're unsure about anything.

Conclusion

The 1997 Nissan 240SX Kouki is a fantastic car with a strong following for good reason. Its rear-wheel drive layout, balanced handling, and readily available aftermarket support make it a popular choice for enthusiasts. By understanding its technical specifications and potential issues, you can make informed decisions about maintenance, repairs, and modifications. Remember to always prioritize safety and reliability when working on your car. Happy wrenching!