130 likes | 622 Views
Tire Pressure Lab. Goal of the Lab. Determine the average tire pressure for a passenger vehicle. Measure the contact patch of the tire. Calculate the aspect ratio of the tire. Use data from lab to determine weight of the car. Tire Pressure.
E N D
Goal of the Lab • Determine the average tire pressure for a passenger vehicle. • Measure the contact patch of the tire. • Calculate the aspect ratio of the tire. • Use data from lab to determine weight of the car.
Tire Pressure • Tire pressure measures the amount of air in your tire per unit volume. • Units: lb/in2 • Method: • Place gauge on uncovered valve stem and release air from tire into gauge. • Read the gauge.
Contact Patch • Def: The area of the tire that comes in contact with the pavement.
Back Side Contact Patch cont…. • Method: Use a ruler to measure the area of the tire that is touching the ground. Side x Back = Area
Contact Patch cont…. • Units: in2 • Under or over inflated tires may result in an incorrect contact patch area!!
Aspect Ratio • Def: A comparison of the tire height to width • Formula:
Aspect Ratio cont…. • Low number= Low Profile Tire Greater width than height
Weight of the Car • Weight is calculated from the contact patch and the tire pressure. • Formula: (Contact Patch in2 x 4 ) x (tire pressure lb/in2)
Rim Size in inches Aspect Ratio Type of tire Width in mm Tire Serial Numbers • P 185 80 R 14