How to VVT Swap your Miata | Engine & Chassis

Introduction

This tutorial will guide you through the process of performing a VVT (Variable Valve Timing) swap on your Miata. This upgrade can enhance your engine's performance and efficiency. The steps outlined here are based on a detailed YouTube video by Napp Motorsports, which covers the necessary hardware, wiring, and installation procedures.

Step 1: Gather Necessary Sensors and Hardware

Before starting the swap, collect all essential components to ensure a smooth installation.

• Sensors Needed:

  • Cam Position Sensor Plug (CONN-75794)
  • Crank Position Sensor Plug (CONN-75759)
  • NB TPS Plug (Throttle Position Sensor) (CONN-75796)
  • NB IACV Plug (Idle Air Control Valve) (CONN-75770)
  • VVT Plug (CONN-75734)

• Additional Hardware:

  • VVT solenoid
  • Appropriate wiring harnesses

Step 2: Prepare Clutch and Flywheel

Ensure your Miata is equipped with the correct clutch and flywheel to accommodate the VVT engine.

• Installation Steps:
  • Remove the existing clutch and flywheel.
  • Install the new flywheel, ensuring it is properly aligned.
  • Install the clutch, making sure it is seated correctly against the flywheel.

Step 3: Install Engine Mounts

Properly secure your engine with the right mounts.

• Installation Tips:
  • Use OEM or high-quality aftermarket engine mounts for better stability.
  • Ensure all bolts are tightened to the manufacturer's specifications.

Step 4: Wire Sequential Fuel Injection and VVT Solenoid

Correct wiring is crucial for the engine's performance.

• Wiring Steps:
  • Connect the sequential fuel injection wires according to the wiring diagram.
  • Connect the VVT solenoid wire, ensuring a secure connection.

Step 5: Install Throttle Cable

Ensure smooth throttle operation with the correct cable installation.

• Installation Instructions:
  • Route the throttle cable from the pedal to the throttle body.
  • Adjust the cable tension for optimal responsiveness.

Step 6: Ignitor Delete and Coil-on-Plug Preparation

Simplify your ignition system by deleting the ignitor.

• Steps to Follow:
  • Disconnect the ignitor.
  • Prepare the wiring for the coil-on-plug setup.

Step 7: Handle Wideband Wiring

Install a wideband O2 sensor for better fuel management.

• Wiring Trick:
  • Connect the wideband sensor to the ECU.
  • Ensure proper grounding to avoid signal interference.

Step 8: Configure Chassis Harness for Injection and VVT

Integrate your chassis harness with the new engine wiring.

• Steps to Integrate:
  • Verify all connections between the chassis and engine harness.
  • Ensure that the fuel injection and VVT connections are secure.

Step 9: Wire Alternator and Starter

Correct wiring of the alternator and starter is essential for engine operation.

• Wiring Instructions:
  • Connect the alternator following the wiring diagram.
  • Ensure starter connections are tight and secure.

Step 10: Manage Ground Wires

Proper grounding is critical for electrical systems.

• Grounding Steps:
  • Clean the grounding points on the chassis.
  • Attach ground wires securely to prevent electrical issues.

Step 11: Revisit Throttle Cable Installation

Double-check the throttle cable for any issues.

• Final Check:
  • Ensure the throttle cable is free of kinks and properly tensioned.

Step 12: IAT Sensor Wiring Trick

Improve air intake temperature sensor connectivity.

• Wiring Instructions:
  • Connect the IAT sensor to the appropriate plug.
  • Ensure it is positioned correctly for accurate readings.

Step 13: Wire Cam and Crank Sensors

Accurate sensor readings are vital for engine performance.

• Wiring Steps:
  • Connect the cam and crank position sensors to the ECU.
  • Verify that all connections are secure.

Step 14: Wire TPS and IACV

Connect the throttle position and idle air control valves.

• Installation Instructions:
  • Ensure TPS and IACV wiring is connected to the correct plugs.
  • Check for any loose connections.

Step 15: Setup Fuel Rail Options and Routing

Plan your fuel delivery system carefully.

• Routing Tips:
  • Ensure that fuel lines are routed safely away from heat sources.
  • Use high-quality fuel rail options for better performance.

Step 16: Route Vacuum Lines

Proper vacuum routing is essential for engine efficiency.

• Routing Steps:
  • Route vacuum lines according to the engine diagram.
  • Ensure there are no leaks or kinks in the lines.

Conclusion

Completing a VVT swap in your Miata can significantly enhance its performance. Ensure you follow each step carefully, from gathering the necessary components to wiring and routing. By adhering to this guide, you can achieve a successful installation and enjoy the benefits of improved engine efficiency. For further resources, consider checking the VVT Swap Mega Thread and related links for additional guidance.