The McLaren Senna GTR at the Geneva Motor Show is technically a concept. However, it gets a spot on this list because the British brand definitely intends to build the track-oriented model.
This is also the first model on this list where we can't entirely trust the output but not for the reasons that you might expect. For now, McLaren says the Senna GTR has “at least” 825 horsepower. However, its production doesn't begin until 2019, which gives the company around a year to further develop the powerplant. By that time, the engine could be even more powerful.