If a car were to accelerate at a constant 1g for 1/4 mile, it would take something like 9 sec., and it would be traveling ~150 MPH at the end. For a while many years ago it was thought those numbers would never be bettered, because to accelerate at 1g the coef. of friction between the tires and the strip would have to be 1.0, and the common physics books said that was the "upper theoretical limit".
But hot-rodders didn't always know the physical laws, and now funnies and top fuelers run well over 300 mph and ~4.5 sec. So *you* figure out the g force and COF!