Car Tuning Aerodynamics and Body Styling 3 — Questions and Answers
Question 1: What is the aerodynamic disadvantage of wide fender flares that extend beyond the original body line?
- They reduce the car's turning radius
- They increase frontal area and aerodynamic drag (Correct answer)
- They lower the center of gravity
- They weaken the suspension mounting points
Correct answer: They increase frontal area and aerodynamic drag
Wide flares push the bodywork outward, increasing the frontal cross-section that must push through air, raising drag.
Question 2: Which material is preferred for high-performance body kits because it offers the best strength-to-weight ratio?
- ABS plastic
- Fiberglass
- Carbon fiber reinforced polymer (CFRP) (Correct answer)
- Sheet aluminum
Correct answer: Carbon fiber reinforced polymer (CFRP)
CFRP combines extremely high tensile strength with very low mass, making it the top choice for weight-critical aerodynamic components.
Question 3: A gurney flap is a small vertical tab added to the trailing edge of a wing. What does it do?
- Reduces wake turbulence to lower drag
- Increases effective angle of attack and downforce without moving the entire wing (Correct answer)
- Deflects air away from the rear diffuser
- Acts as a brake light mount
Correct answer: Increases effective angle of attack and downforce without moving the entire wing
A gurney flap stalls the lower surface flow, effectively increasing camber and boosting downforce with minimal added drag.
Question 4: What is 'aero balance' in the context of car tuning?
- Equal tire pressure at all four corners
- The front-to-rear distribution of aerodynamic downforce (Correct answer)
- The weight difference between left and right sides of the body
- The balance between engine power and aerodynamic drag
Correct answer: The front-to-rear distribution of aerodynamic downforce
Aero balance describes how much total downforce acts on the front versus rear axle, critically affecting high-speed handling.
Question 5: Why do some racing-inspired builds use a 'ducktail' or short trunk spoiler instead of a tall wing?
- Ducktails are cheaper to manufacture than wings
- They add downforce with less drag penalty than a high-mounted wing (Correct answer)
- They are required by US street-legal regulations
- They provide more visual impact for show cars
Correct answer: They add downforce with less drag penalty than a high-mounted wing
A ducktail spoiler redirects rearward airflow at a low angle, generating modest downforce while keeping the drag increase small.
Question 6: What is the function of brake-duct scoops integrated into the front bumper of a performance car?
- Channel cool ambient air directly to front brake rotors and calipers (Correct answer)
- Increase front downforce by acting as additional splitters
- Feed fresh air to the engine through the bumper opening
- Reduce aerodynamic lift by creating a low-pressure zone
Correct answer: Channel cool ambient air directly to front brake rotors and calipers
Dedicated brake duct scoops capture ram air and route it through hoses to the brake assembly to prevent brake fade during hard driving.
Question 7: On a front-wheel-drive tuner car, why is rear downforce alone potentially dangerous without matching front downforce?
- It causes the front wheels to spin excessively
- It shifts the car's balance rearward, reducing front grip and causing understeer (Correct answer)
- It overloads the rear suspension springs
- It blocks exhaust gas flow
Correct answer: It shifts the car's balance rearward, reducing front grip and causing understeer
Adding rear downforce without balancing the front increases the proportion of weight on the rear axle, lightening front grip and promoting severe understeer.
Car Tuning Aerodynamics and Body Styling 3
What is the aerodynamic disadvantage of wide fender flares that extend beyond the original body line?