Physics

Physics is a science where we work with matter and energy and their interactions in the fields of mechanics. We are working with physics, for instance, every time we change gear ratios in our cars or the driveshaft alignment. We are changing the mechanical advantage of the engine in its relationship to accelerating the car. We do follow the SM in determining the correct gear ratio for our car at a particular racetrack.

Physics is also applied when tuning our engine for maximum horsepower or optimizing the torque curve. We observe how quickly we accelerate down the straight-aways and compare our times with the competition. If we are deficient, we work to make improvements.

Adjusting brake bias through a mechanical leverage system or by installing different diameter master cylinders is a good example of using the laws of physics to adapt our race cars to the forces of deceleration.

Settings such as bumpsteer, roll steer, and Ackermann, if not correct, can ruin an otherwise great spring and moment center combination. We use various instruments to evaluate our suspension geometry such as laser alignment tools, bumpsteer gauges and computerized racing programs.

Dynamics

This is a branch of mechanical engineering where we deal with forces and how they act on an object, or race car in our example, and how the car reacts to those forces. Our quest for higher performance must involve the study of dynamics and how our car is able to conform to the various forces it encounters lap after lap.

We have tools we need to study exactly what might be affecting our race car. These tools include tire temperature gauges, pressure gauges, tread depth gauges, shock travel indicators, and up to and including data acquisition. Of equal use are computer programs that tell us our moment center location and camber change characteristics as well as the dynamic balance of the car.

We are continually working to improve the dynamic condition of our race cars to make sure the four tires are working as hard as possible. Then we will be as fast as we can be relative to the limitations of tires, track surface conditions and available horsepower.

The word failure should never be used to describe an experiment that does not produce the desired results. We succeed in ...

Aerodynamics

Aerodynamics is a branch of racing dynamics that deals with the movement of air across the race car body and the pressures exerted on it while the car is in motion. We now know much more about how aero creates downforce. We use that knowledge to construct our cars so that we can take advantage of higher amounts of downforce to add "load" to the tires without adding weight to the car.

Stock cars often top 100 mph, even on the shortest racetracks. Even at the legal speed limit of 70 mph on the highway, we can stick our hand out of the window and feel the tremendous force of the rush of air. When we harness this force, we improve the way our cars grip the surface of the racetrack.

Thermodynamics is an area of Physics that deals with the mechanical action or relations of heat. Smokey developed an extremely high degree of knowledge of thermodynamics and could converse with the best PhDs around. He helped to develop advanced methods and technology related to the internal combustion engine within a small and underfinanced shop in Daytona Beach, Florida. It was referred to as his "inner-sanctum" because when he was on a quest, he became completely absorbed in the work. We may never find a better example of a racing scientist.

Smokey had a long list of accomplishments and successes. Even with his relatively low budgets and simple tools, he made remarkable discoveries that any well financed institution or corporation would be proud of.

The racing engine, as I learned in my thermodynamics class, is merely a heat exchange device that converts fuel into heat and then into energy. The more efficiently we can cause this exchange, the more energy we can produce, which is measured in our engines as horsepower and torque. When we tune the spark advance timing or carburetor air/fuel ratio, we are refining the process of heat exchange.

Outside the engine compartment, the brakes are heat generators too. The brakes on our cars convert energy to heat to help stop the car. Excessive heat is not desirable and can cause the brakes to fail. The disc brake system was incorporated into many race car designs to overcome deficiencies in the older production drum brake systems.

Along with that change, we have developed better compounds for use in our brake pads and improved rotor designs that will endure high heat and wear and that are designed to help vent heat away from the pads. Racers invented brake fluid cooling systems that recirculate and cool the fluid. Along the way, there has been further development to produce more heat resistant brake fluids.

Tire performance involves heat too. The tires benefit from heat so they can be more compliant to the racetrack. Without heat, the various internal compounds would not work to soften the rubber to help make the tire adhere to the track. So we read the heat in the tires and use that data to tell us how efficiently the tire is working. We make changes to the setup, geometry and air pressures largely based on these tire heat readings.

Hydraulics

Hydraulics is another branch of science that deals with practical applications of a liquid in motion. Our race car has several hydraulic systems. Water flows to the engine through the water pump then out to radiator and back. Oil flows from the oil pan or reservoir to the bearings, pistons, valves, and more and through a cooler and back to the engine. Brake fluids also flow from the master cylinder to the slave cylinder, or brake calipers, and absorb heat and moisture which affects that system.

A lot of research has taken place over the years to improve the cooling of our motors, the lubrication of the engine and the efficiency and longevity of our brake systems. When we modify our radiators, develop water "wetter" heat reducing liquids that can be mixed with the coolant, or regulate the rate of flow of the coolant through the radiator and motor, we are experimenting in the field of science known as hydraulics.