Unfortunately not!
Gran Turismo 6 was released back on December 6, 2013.
To date, the McLaren P1 is not yet available in Gran Turismo 6.
Gran Turismo 6 - 2013 VG is rated/received certificates of: Singapore:G
The 2011 BMW 5-Series-Gran-Turismo has an inline 6 engine.
The 2012 BMW 5-Series-Gran-Turismo has an inline 6 engine.
The 2014 BMW 5-Series-Gran-Turismo has an inline 6 engine.
The 2013 BMW 5-Series-Gran-Turismo has an inline 6 engine.
The 2010 BMW 5-Series-Gran-Turismo has an inline 6 engine.
The 2014 BMW 5-Series-Gran-Turismo is 6 ft. 2.8 in. (74.8 in.)12 total speakers wide.
The 2012 BMW 5-Series-Gran-Turismo is 6 ft. 2.8 in. (74.8 in.)12 total speakers wide.
The 2010 BMW 5-Series-Gran-Turismo is 6 ft. 2.8 in. (74.8 in.)12 total speakers wide.
The 2013 BMW 5-Series-Gran-Turismo is 6 ft. 2.8 in. (74.8 in.)12 total speakers wide.