240sx S13 Performance Parts: Best Upgrades List
The Nissan 240SX S13, a lightweight, rear-wheel-drive platform, remains a favorite among automotive enthusiasts for its potential as a drift weapon, a track day warrior, or simply a fun street car. Its robust SR20DET (in JDM models) and KA24DE engines, combined with a relatively simple chassis, make it an ideal candidate for performance upgrades. However, wading through the vast aftermarket can be daunting. This guide provides an analytical look at essential upgrades, explaining *why* they work and what performance gains you can realistically expect.
Engine Performance: Breathing Easier and Making More Power
The heart of any performance build is, of course, the engine. While the KA24DE offers a solid foundation, the SR20DET is the more common platform for serious power gains. We'll cover upgrades applicable to both, noting the differences where relevant.
Intake and Exhaust Systems
Improving airflow is the foundation of any performance upgrade. Think of your engine as an air pump; the more efficiently it can breathe, the more power it can generate. Restricted intakes and exhausts choke the engine's potential.
- Intake: A cold air intake (CAI) relocates the air filter away from the engine bay, drawing in cooler air. Cooler air is denser, containing more oxygen per unit volume, leading to a more efficient combustion. However, be mindful of potential hydro-locking issues in wet climates if the filter is positioned too low. Short ram intakes (SRI) are an alternative, positioned higher in the engine bay but potentially drawing in warmer air. The best option depends on your climate and driving conditions. Consider a quality air filter from brands like K&N or AEM for improved filtration and airflow.
- Exhaust: The stock exhaust system is typically restrictive. Upgrading to a larger diameter exhaust, often 2.5" to 3" for turbo applications and 2.25" to 2.5" for naturally aspirated, reduces backpressure. A less restrictive exhaust allows the engine to expel exhaust gases more easily, freeing up horsepower. A full exhaust system typically consists of:
- Downpipe (Turbo Models): Replaces the restrictive factory downpipe, which is located immediately after the turbocharger. A larger diameter downpipe with a high-flow catalytic converter significantly reduces backpressure.
- Catalytic Converter: Choose a high-flow catalytic converter to maintain emissions compliance without sacrificing performance.
- Cat-Back Exhaust: Replaces the exhaust system from the catalytic converter back. Look for systems with smooth bends and minimal restrictions.
Turbocharger Upgrades (SR20DET)
For SR20DET engines, upgrading the turbocharger is a common path to significant power gains. The stock T25 or T28 turbocharger is relatively small and reaches its limits at moderate boost levels. Larger turbochargers can flow more air, enabling higher horsepower figures. However, simply slapping on a bigger turbocharger isn't enough; supporting modifications are essential.
- Fuel Injectors: Larger fuel injectors are needed to supply the engine with sufficient fuel to match the increased airflow from the larger turbo. Common sizes range from 550cc to 1000cc, depending on the desired power output.
- Fuel Pump: The stock fuel pump may not be able to supply enough fuel to the larger injectors, especially at higher boost levels. An upgraded fuel pump, such as a Walbro 255 LPH, is a must.
- ECU Tuning: This is *absolutely critical*. The stock ECU cannot properly manage the increased airflow and fuel delivery of a larger turbocharger. An aftermarket ECU or a professionally tuned stock ECU is essential to ensure proper air/fuel ratios and prevent engine damage. Popular aftermarket ECUs include AEM Infinity, Haltech Elite, and Link ECU.
- Intercooler: A larger intercooler is required to cool the increased volume of air being compressed by the larger turbo. A front-mount intercooler (FMIC) is the most common and effective option, offering better cooling than the stock side-mount intercooler.
Camshafts
Upgrading the camshafts can alter the engine's valve timing, improving airflow and power output. Aggressive camshafts with higher lift and longer duration can significantly increase horsepower, but they may also sacrifice low-end torque and idle quality. Choose camshafts that are appropriate for your driving style and intended use.
Engine Management
We touched on this with turbo upgrades, but it deserves its own section. The ECU is the brain of the engine, controlling fuel delivery, ignition timing, and other critical parameters. An aftermarket ECU or a professionally tuned stock ECU is essential for maximizing performance and ensuring engine reliability, especially with any significant modifications. Aftermarket ECUs offer greater flexibility and control over engine parameters, allowing for precise tuning and optimization.
Suspension and Handling: Putting the Power to the Ground
Increased power is useless if you can't control the car. Upgrading the suspension and handling is crucial for improving the 240SX's performance on the track or on the street.
Coilovers
Coilovers replace the stock struts and springs with adjustable dampers and springs. They allow you to fine-tune the ride height, damping, and spring rates, optimizing the suspension for your specific needs. Look for coilovers with adjustable ride height and damping to allow for maximum flexibility. Spring rates should be chosen based on your driving style and the intended use of the car. Stiffer spring rates are generally preferred for track use, while softer spring rates are better suited for street driving.
Sway Bars
Sway bars (also known as anti-roll bars) connect the left and right wheels, reducing body roll during cornering. Upgrading to stiffer sway bars can significantly improve handling and reduce understeer. Adjustable sway bars allow you to fine-tune the handling balance of the car.
Suspension Bushings
The stock rubber suspension bushings can flex and deform under load, leading to imprecise handling. Replacing the rubber bushings with polyurethane or spherical bearings can significantly improve handling and responsiveness. Polyurethane bushings are a good compromise between performance and comfort, while spherical bearings offer the ultimate in performance but can be harsh for street driving. Consider a full bushing kit for a noticeable improvement.
Steering Angle Kit
For drifting, a steering angle kit is essential. These kits increase the maximum steering angle, allowing for greater control during drifts. Steering angle kits typically include modified knuckles, tie rods, and other components.
Brakes: Stopping Power Matters
With increased power comes the need for improved braking. The stock brakes on the 240SX are adequate for street use, but they can quickly overheat and fade under hard driving conditions.
Brake Pads
Upgrading to performance brake pads is the first and most cost-effective way to improve braking performance. Performance brake pads offer a higher coefficient of friction and can withstand higher temperatures than stock pads. Choose brake pads that are appropriate for your driving style and intended use. Aggressive track pads may be noisy and dusty for street use.
Brake Rotors
Upgrading to slotted or drilled brake rotors can improve braking performance by increasing the surface area and allowing for better heat dissipation. However, drilled rotors can be prone to cracking under extreme heat. Slotted rotors are a good compromise between performance and durability.
Brake Lines
Stainless steel brake lines replace the stock rubber brake lines, which can expand under pressure, leading to a spongy brake feel. Stainless steel brake lines are more resistant to expansion, providing a firmer and more responsive brake pedal feel.
Big Brake Kit (BBK)
For serious track use, a big brake kit is a worthwhile investment. BBKs typically include larger rotors, calipers with more pistons, and upgraded brake pads. They offer significantly improved braking performance and heat capacity, reducing brake fade and improving stopping power.
Drivetrain: Transferring Power Efficiently
Upgrading the drivetrain is essential for handling increased power and improving reliability.
Clutch
The stock clutch is often inadequate for handling the increased torque of a modified engine. Upgrading to a stronger clutch is essential to prevent slippage and ensure reliable power transfer. Choose a clutch that is appropriate for your power level and driving style. A sprung clutch disc is recommended for street use to reduce drivetrain noise and vibration.
Limited Slip Differential (LSD)
The stock open differential allows the wheels to spin independently, which can lead to wheel spin and loss of traction. A limited slip differential (LSD) locks the wheels together to some degree, improving traction and acceleration, especially in cornering. There are several types of LSDs available, including clutch-type, Torsen-type, and viscous-type. Clutch-type LSDs offer the most aggressive locking action, while Torsen-type LSDs are smoother and more predictable. Viscous-type LSDs are less common and offer a less aggressive locking action.
Driveshaft
With increased power, the stock driveshaft can become a weak point. Upgrading to a stronger driveshaft, such as a one-piece aluminum or carbon fiber driveshaft, can improve reliability and reduce drivetrain weight.
Conclusion
Upgrading a Nissan 240SX S13 for performance is a rewarding endeavor. However, it's crucial to approach it with a plan and a budget. Prioritize upgrades based on your needs and goals, and always ensure that supporting modifications are made to complement each upgrade. Remember, a well-engineered and balanced car is always faster and more enjoyable than one with simply the most horsepower. By carefully selecting the right parts and tuning them properly, you can transform your 240SX into a formidable performance machine.