SD Sports (Apocalypse)
Larger anti-grav units give more speed and acceleration for Hovercars and other small airborne vehicles.
Source: X-COM Apocalypse Ufopedia
The top of the line Superdynamics engine for very small airborne vehicles. It comes as standard on the Hovercars and is the largest engine that can be fitted to a Hoverbike. It is also used by various civilian vehicles.
This is the preferred engine for Hoverbikes as it provides excellent performance and acceleration.
If there is a shortage of SD Sports engines for purchase, one can buy a Phoenix Hovercar and rip out the engine, selling the Hovercar afterwards.