Guide To Swapping A Chevrolet 350 Small Block Into A Nissan 240sx

The Nissan 240SX, renowned for its lightweight chassis and sporty handling, has long been a favorite among drifting and performance enthusiasts. While the factory SR20DET and KA24DE engines are capable, some owners seek more power and torque. One popular modification is swapping in a Chevrolet 350 small block V8. This guide provides a comprehensive overview of what’s involved in swapping a Chevy 350 into a Nissan 240SX.

Why Swap a Chevy 350 into a 240SX?

The allure of a 350 swap is multifaceted. Here are some key reasons why people consider this modification:

Increased Power: A well-built 350 can produce significantly more horsepower and torque than the stock engines, dramatically improving acceleration and overall performance.
Affordability: Chevy 350 engines and parts are readily available and relatively inexpensive compared to high-performance imports.
Simplicity: While the swap itself requires considerable effort, the 350 is a mechanically simple engine, making it easier to diagnose and repair compared to more complex modern engines.
Sound: The throaty rumble of a V8 is a sound many find irresistible.

What You'll Need: A Comprehensive Parts List

Successfully swapping a 350 into a 240SX requires a significant investment in parts and modifications. This list outlines the essential components:

Chevrolet 350 Engine: Choose a 350 that suits your budget and performance goals. Consider a crate engine for reliability or a used engine for affordability. Rebuilding a used engine is highly recommended before installation.
Transmission: A robust transmission is crucial to handle the 350's power. Popular choices include the TH350, TH400, or a manual transmission like a T5 or T56. Ensure the transmission is compatible with your engine and driveline.
Engine Mounts: Custom engine mounts are essential to securely position the 350 in the 240SX engine bay. Several aftermarket kits are available specifically for this swap.
Transmission Mount: Similar to the engine mounts, a custom transmission mount will be needed.
Driveshaft: The stock 240SX driveshaft will not work. You'll need a custom-length driveshaft to connect the transmission to the rear differential.
Rear Differential: The stock 240SX differential may not withstand the increased power. Consider upgrading to a stronger unit, such as a Ford 8.8" or a Nissan Z32 differential.
Cooling System: The stock radiator is inadequate for a 350. You'll need a larger aftermarket radiator, electric fans, and custom hoses.
Fuel System: The stock fuel pump and lines will likely need to be upgraded to supply the 350's fuel demands. Consider a high-flow fuel pump, fuel pressure regulator, and larger fuel lines.
Exhaust System: Custom headers and exhaust system are required. Shorty headers are often used for clearance.
Wiring Harness: Integrating the 350's wiring into the 240SX electrical system is a critical step. Aftermarket wiring harnesses are available, or you can modify the existing harness.
Gauges: The stock gauges may not be compatible with the 350. Consider installing aftermarket gauges to monitor engine parameters like oil pressure, water temperature, and voltage.
Power Steering: Adapting the power steering system can be challenging. Some kits retain the stock 240SX power steering pump, while others require a different pump and custom lines.
Brakes: Upgrading the brakes is highly recommended to handle the increased power. Consider larger rotors, calipers, and upgraded brake pads.
Suspension: The added weight of the V8 will affect the car's handling. Upgrading the suspension with stiffer springs and dampers is crucial for maintaining control.
ECU: Aftermarket ECU is recommended to control the engine functions.

Step-by-Step Guide to the Swap

This section provides a general overview of the swap process. Consult with experienced professionals or online forums for detailed instructions specific to your setup.

Preparation: Gather all necessary parts, tools, and information. Thoroughly research the swap and plan each step carefully.
Remove the Old Engine: Disconnect all wiring, hoses, and fuel lines from the stock engine. Remove the engine and transmission from the engine bay.
Clean and Prepare the Engine Bay: Clean the engine bay thoroughly and remove any unnecessary components.
Install Engine Mounts: Install the custom engine mounts onto the 240SX chassis. Ensure they are properly aligned and securely fastened.
Install the Engine: Carefully lower the 350 engine into the engine bay, aligning it with the engine mounts.
Install the Transmission: Attach the transmission to the engine.
Fabricate or Purchase Transmission Mount: Install the transmission mount.
Connect the Drivetrain: Install the custom driveshaft to connect the transmission to the rear differential.
Cooling System Installation: Install the aftermarket radiator, electric fans, and custom hoses.
Fuel System Installation: Install the high-flow fuel pump, fuel pressure regulator, and larger fuel lines.
Exhaust System Installation: Install the custom headers and exhaust system.
Wiring and Electrical: Connect the wiring harness to the engine and integrate it with the 240SX electrical system. Connect the gauges and other electrical components. This is often the most time-consuming step.
Power Steering: Adapt the power steering system.
Braking System Upgrade: Upgrade braking system.
Suspension Upgrade: Upgrade the suspension with stiffer springs and dampers.
ECU Installation: Install and setup the aftermarket ECU.
Testing and Tuning: Once everything is connected, start the engine and check for leaks or problems. Tune the engine for optimal performance.

Considerations and Challenges

Swapping a 350 into a 240SX presents several challenges:

Weight Distribution: The 350 is heavier than the stock engines, which can affect the car's handling. Consider relocating the battery to the rear to improve weight balance.
Clearance Issues: The 350 is larger than the stock engines, which can lead to clearance issues with the hood, exhaust, and other components.
Complexity: This swap is complex and requires significant mechanical knowledge and fabrication skills.
Cost: The total cost of the swap can be substantial, especially if you opt for high-performance parts and professional installation.
Legality: Check your local laws and regulations regarding engine swaps. Some areas require emissions testing and may not allow certain modifications.

Tips for a Successful Swap

Here are some tips to help ensure a successful 350 swap:

Do Your Research: Thoroughly research the swap and gather as much information as possible before starting. Consult with experienced individuals or online forums.
Plan Carefully: Create a detailed plan that outlines each step of the swap. This will help you stay organized and avoid costly mistakes.
Budget Wisely: Develop a realistic budget that accounts for all necessary parts, tools, and labor. Be prepared for unexpected expenses.
Take Your Time: Don't rush the swap. Take your time and pay attention to detail.
Seek Professional Help: If you're not comfortable performing certain tasks, seek professional help from a qualified mechanic or fabricator.
Document Everything: Keep detailed records of all modifications and parts used. This will be helpful for future maintenance and troubleshooting.

Alternatives to a 350 Swap

While a 350 swap is a popular option, it's not the only way to increase the power of a 240SX. Consider these alternatives:

SR20DET Upgrade: Upgrading the stock SR20DET engine with performance parts can significantly increase its power output.
KA24DET Turbo Conversion: Turbocharging the stock KA24DE engine is another way to boost its performance.
LS Swap: LS series engines offer excellent power and reliability, and LS swap kits are available for the 240SX.

Conclusion

Swapping a Chevy 350 into a Nissan 240SX is a challenging but rewarding modification. It can dramatically increase the car's performance and create a unique and exciting driving experience. However, it's essential to carefully consider the costs, challenges, and alternatives before embarking on this project. With proper planning, research, and execution, you can successfully transform your 240SX into a powerful and reliable V8-powered machine. Remember to prioritize safety and legality throughout the process.

Disclaimer: This guide is for informational purposes only. Engine swaps and modifications should be performed by qualified professionals. The author is not responsible for any damages or injuries that may result from following this guide.