more mass needs more force to accelerate at the same rate as a lighter object period. race a sportbike with 2 people. that is an extreme case as another 200lb person is a higher percentage increase to a few hundred pound bike than 200lbs is to a 2800lb car so it is quite a bit more noticeable to the driver. like kento said aero is very important remember the benz race cars flying over trees at le mans?

 

Yea...that and the Porsche that did a backflip But I thought those 2 cases were because those cars are so light and travel so fast that the lift generated under the nose of the car was tremendous, prob. from something even as simple as hitting a bump, causing the front end to lift up....