Mazda RX-7 FD

How much does a Scoot four-rotor conversion cost for a Mazda RX-7 FD?

Updated June 2026

We do have general cost estimates for 4-rotor conversions in an FD RX-7, as well as a few technical details regarding the Scoot setup.

For the Scoot 4-rotor specifically, it produces around 400 horsepower and is uniquely able to run the stock FD transmission due to its linear torque delivery at that power level 2.

If you are planning a 4-rotor build for your FD, this is an Expert level project that requires heavy custom fabrication. Here is a breakdown of what you can generally expect to spend:

  • The Engine: A fully built 4-rotor engine sourced from custom builders (such as those in New Zealand) runs about $26,000. If you are building it yourself, a custom 4-rotor eccentric shaft/crank kit alone typically costs between $8,000 and $9,000 2.
  • DIY Approach: If you handle 100% of the labor yourself—including all custom fabrication, tuning, and engine assembly—and start with a rolling chassis, it is possible to complete the build for $15,000 to $25,000 2.
  • Complete Build: Once you factor in the engine, a standalone fuel management system, custom intake and exhaust fabrication, subframe modifications, and labor from a shop, a complete naturally aspirated 4-rotor build is estimated to cost between $35,000 and $50,000+ 2.

While the stock transmission holds up to the ~400hp Scoot build, higher-horsepower 4-rotor setups (600+ hp) will require serious drivetrain upgrades, such as a built Tremec T56 transmission and a Ford 9-inch rear end, which will further increase the total cost 2.

This answer was generated by GarageBot's AI from enthusiast forum discussions. Always verify torque specs and safety-critical procedures against the factory service manual before working on your car.

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