I have no issue pushing my F2000 to the ragged edge all day, a few laps as passenger in ANY car and I get nauseousI usually do 3 laps with a passenger - that helps avoid the carsickness problems.
Funny story: one time at Thermal I took a friend of mine who's a serious enthusiast driver for 3 laps in the 488 GT3. At the end of 3 laps he was still giving a big thumbs up, so we did three more, at race pace. We pulled into the pits after 6 laps, he jumped out of the car, ripped off his helmet, ran to the bushes, threw up, and then turned to me and said
"BEN, this car is VIOLENT. And you, YOU are a violent person!!! I did not know this about you."
And we both started laughing. So now I keep it to 3 laps.