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My dad, brothers and I wanted to go to IMSA at VIR in August. We'd likely be going for only one day. I'm having a hard time figuring out what the different classes/cars are in each race. Could someone tell me what are the cars for the VP Racing, Michelin Pilot Challenge, Weathertech, Michelin GT challenges?

We're interested in multi-class racing and GT3 racing. Any suggestions as to whether Saturday or Sunday would be best for us?

Edit: Thank you everyone for the responses! Sounds like Sunday is the day to go