Ganked from wikia:
This car is used in the Time Limited Serie "McLaren 675LT Championship". ( Started 1st of November 2016; Duration: 4 days ).
Pr66 to win the car. 7313222 is 191 gold and i think it's the cheapest way
The car is also used in the 4.7.2 introduced career series "Road Masters",
you'll need the McLaren with a PR of 70.0. Audi and Lexus can't reach that.