Real-world Results: 200-plus Hp Gains with a 13b-rew Rotary Swap in a Miata

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The Mazda Miata is well-known for its lightweight design and exceptional handling. However, enthusiasts often seek ways to enhance its performance beyond the factory specifications. One popular modification is the 13B-REW rotary engine swap, which can yield impressive power gains. This article explores the real-world results of this swap, highlighting the benefits, challenges, and considerations for those looking to undertake such a project.

Understanding the 13B-REW Rotary Engine

The 13B-REW is a two-rotor engine developed by Mazda, primarily used in the RX-7. Known for its lightweight and compact design, the 13B-REW can produce significant power relative to its size. Key features include:

  • Displacement: 1.3 liters
  • Power Output: Approximately 250-280 hp in stock form
  • Redline: 9,000 RPM

Why Swap a 13B-REW into a Miata?

Swapping a 13B-REW into a Miata can provide several advantages over the stock engine. These include:

  • Weight Distribution: The rotary engine’s compact size helps maintain the Miata’s balanced weight distribution.
  • Power-to-Weight Ratio: The significant horsepower increase enhances the Miata’s already impressive power-to-weight ratio.
  • Unique Sound: The distinctive sound of the rotary engine adds character to the driving experience.

Real-World Performance Gains

Enthusiasts who have completed the 13B-REW swap report substantial performance improvements. Here are some real-world results:

  • Power Gains: Many users report gains of over 200 horsepower.
  • Acceleration: 0-60 mph times can drop to under 4 seconds.
  • Top Speed: Increased top speeds, often exceeding 150 mph.

Challenges of the Swap

While the 13B-REW swap offers exciting benefits, it also comes with challenges that potential swappers should consider:

  • Engine Mounting: Custom mounts are often required for proper fitment.
  • Wiring and Electronics: Integrating the rotary engine’s electronics can be complex.
  • Cooling Requirements: Upgraded cooling systems may be necessary to handle the increased power.

Additional Modifications

To fully realize the potential of a 13B-REW swap, additional modifications may be necessary. These can include:

  • Upgraded Fuel System: A higher-capacity fuel pump and larger injectors may be needed.
  • Exhaust System: A performance exhaust system can help improve airflow.
  • Suspension Upgrades: Enhanced suspension components can improve handling to match the increased power.

Conclusion

Swapping a 13B-REW rotary engine into a Mazda Miata can yield remarkable performance gains, often exceeding 200 horsepower. While the process comes with its challenges, the rewards in terms of driving experience and power can be well worth the effort. For enthusiasts looking to push the limits of their Miata, the rotary swap presents an exciting opportunity to transform their vehicle into a high-performance machine.