When a car makes a turn, its occupants feel themselves pushed to the side, perpendicularly to the direction the car travels. Lateral acceleration measures the force acting on them. People informally refer to this as the "g-force" acting on the passengers. Calculate it using the radius of the vehicle's full lap and the time it takes to complete one.
Square the time it takes the car to complete a lap. If it takes 9 seconds:
9 ^ 2
Multiply 1.227 by the lap's radius. If the radius if 100 feet:
1.227 * 100
Divide your answer by your answer from step 1.
122.7 / 81
\= 1.51 feet per second squared