Engine Conversions

Engine Conversions

We offer performance improvement by allowing you to put the 20B 3 rotor in a 2 rotor Mazda FD3S.
Our kits are exceptionally well made and well thought through for the Mazda FD3S owner. We have skillfully engineered our installation kit to eliminate chassis modifications and significant power steering rack modifications to accomodate the 20B.

Both our kits include everything you require. We do need a few components off your car so we can make minor changes to those - rather than you making major changes to the chassis.

3-Rotor Conversion | FD3S Third Gen

20b Conversion Base Kit for FD3S Third Gen Rx-7
Defined Autoworks still remains the one and only to produce a 20b conversion kit that keeps the stock subframe! Unlike everyone else, the steering rack is un-moved resulting in perfect handling the way Mazda intended it. No bump steer corrections, sway bar relocations, or danger of weak welds on a modified subframe. Safer, legal in all forms of racing, and better in every way. Our kit makes the 20b bolt into the FD chassis. Stock Hood fits perfect, no triming needed. We do require three parts to be sent in for modification- Stock 20b oil pan, the Rx7 Power steering bracket, and the Rx7 steering rack. Dont worry, only a pressure fitting is moved on the steering rack. This base version deletes Air conditioning, but keeps power steering. If you want to keep both a/c and p/s take a look at our Deluxe 20b conversion kit!

Requires shortened intake manifold, available separately

  • FD3S Third Gen RX7
  • Keeps Stock Subframe
  • No Chassis Mods
  • Keeps Steering Rack
  • Keeps Stock Hood
  • No Bump Steer
  • No A/C on Base Kit - See Deluxe Kit Below
  • $1,670

3-Rotor Conversion | FD3S Third Gen

20b Conversion Deluxe Kit for FD3S Third Gen Rx-7
Defined Autoworks still remains the one and only to produce a 20b conversion kit that keeps the stock subframe! Unlike everyone else, the steering rack is un-moved resulting in perfect handling the way Mazda intended it. No bump steer corrections, sway bar relocations, or danger of weak welds on a modified subframe. Safer, legal in all forms of racing, and better in every way. Our kit makes the 20b bolt into the FD chassis. Stock Hood fits perfect, no triming needed. We do require three parts to be sent in for modification- Stock 20b oil pan, the Rx7 Power steering bracket, and the Rx7 steering rack. Dont worry, only a pressure fitting is moved on the steering rack. This is the deluxe version, which will keep air conditioning and power steering. Now there is no reason to buy a "subframe kit", ours keeps the stock one untouched!

Requires shortened intake manifold, available separately

  • FD3S Third Gen RX7
  • Keeps Stock Subframe
  • No Chassis Mods
  • Keeps Steering Rack
  • Keeps Stock Hood
  • No Bump Steer
  • A/C included
  • $2.070

Questions? Give us a call - We talk Rotary