SD Turbo (Apocalypse)
A medium sized of engine sold by Superdynamics. It is a 2x4 size which is the largest engine that can go into a Phoenix Hovercar, thus it is the only engine which is suitable for this vehicle. The power and acceleration is good for a Hovercars, but lacking if used in the Valkyrie Interceptor or Hawk Air Warrior .
If unable for purchase, then buy up the Valkyrie Interceptor and rip out the engine. Sell the Valkyrie afterwards.