the whole "car vs. bike" thing has long been answered.
it's as much about the performance of the vehicles as the type of track/roadway.
wherever the track/roadway requires combination of braking/accel AND steering inputs at the SAME TIME...a car will almost always outperform a bike. having four wheels allows more room for error, and consequently more at-the-limit time spent. that's why you never see skidpad figures for a bike, for when the bike reaches the limit...the rider is off and the bike is totaled.
whenever the course allows these two things to be separated...a bike will CRUSH a car through sheer power to weight and weight-vs.-contact patch advantage.
just a function of the way the vehicles operate.
moral of the story, don't mess with a car on tight/twisty roads. they have more room for error and will stay on you. if it's turns PLUS long straights in between them...have at it. they'll never catch you blasting out of the turns.