There will be F1 cars in GT3, a 1991 McLaren and a late '80's Lotus I think but I think that only the testers had F1 cars in GT and GT2 to test the tracks.
I have both the Lotus and the McLaren. The Lotus is back from the days when turbos were allowed. It has 888 horsepower and weighs 540 kilograms. Downforce is a wonderful thing.
The McLaren is 690 horsepower with about the same weight. Both will blow anything out of the water, and they run about 9 flat in the quarter.
I'm calling some buddies today, we're going to race, but you have to have a stock car