Car Tuning Aerodynamics and Body Styling 4

Question 1

What is 'drag coefficient' (Cd) and why do tuners care about it?

Accepted Answer

A dimensionless number quantifying how efficiently a shape moves through air

Answer

Cd quantifies aerodynamic drag relative to frontal area and air density; a lower Cd means less power wasted pushing air aside at speed.

Question 2

Which type of hood modification helps both cool the engine and reduce hood lift at high speed?

Accepted Answer

A functional hood scoop with a forward-facing opening

Answer

A forward-facing hood scoop uses ram pressure to force cool air into the engine bay, while the venting reduces positive pressure that would lift the hood.

Question 3

What does 'rake' refer to when setting up the aerodynamics of a race-inspired build?

Accepted Answer

The angle at which the car sits lower at the front than the rear

Answer

Rake means the car is pitched with the nose lower than the tail, which accelerates underbody airflow and enhances diffuser efficiency.

Question 4

Why might a tuner choose polyurethane (PU) bumpers over fiberglass for a street-driven car?

Accepted Answer

Polyurethane flexes on minor impact rather than cracking or shattering

Answer

PU is flexible and absorbs low-speed impacts without cracking, making it practical for street use where minor bumps are common.

Question 5

What is the aerodynamic role of side skirts on a modified car?

Accepted Answer

Increase ground effect by blocking high-pressure air from rushing under the car

Answer

Side skirts seal the gap between the lower body and ground, maintaining a low-pressure zone under the car for improved ground effect downforce.

Car Tuning Practice Test

Car Tuning Practice Test

Car Tuning Aerodynamics and Body Styling 4