P1- Dyson
P2- (not sure)
GTS- #4 Corvette
GT- Ferrari

P1-Champion Audi. The Audi has better tourque off the low speed corners, two of which at Portland lead on to long straights. There's also a lot of curb hopping, which is not good for the more fragile MG Lola.
P2- the #56 car. It's the only one that's shown any speed all season.
GTS- #4 Corvette. The Ferraris are gone, and the Lamborghinis aren't up to speed yet.
GT- #45 Flying Lizard Porsche. They've unexpectedly got the Job cars trying to figure out how to go faster.