McLaren is now putting prototypes of the car through a combined 18,500 miles of on-track testing.
This race-spec version of the McLaren 720S will enter GT3 racing championships in 2019.
Compared to the road car, McLaren says 90 percent of the 720S GT3's parts are new or "optimized."
Power comes from a racing-modified version of the regular car's twin-turbo 4.0-liter V8.
The 720S GT3 has unique bodywork, including that giant rear wing.
Safety upgrades include a roll cage, a carbon-Kevlar seat with a six-point harness and a fire-extinguishing system.
Each 720S GT3 will cost customer race teams a cool $564,000.