1. What is the Horsepower to Speed Equation?

The horsepower to speed equation estimates vehicle speed based on horsepower, weight, and a constant factor. It provides a theoretical maximum speed based on power-to-weight ratio and aerodynamic drag factors.

2. How Does the Calculator Work?

The calculator uses the speed equation:

Where:

• \( hp \) — Engine horsepower
• \( Weight \) — Vehicle weight in pounds
• \( Constant \) — Aerodynamic drag factor (typically around 0.000023)

Explanation: The equation accounts for the cubic relationship between power and speed due to increasing aerodynamic drag at higher speeds.

3. Importance of Speed Calculation

Details: Understanding the theoretical speed potential helps in vehicle design, performance tuning, and comparing different vehicle configurations.

4. Using the Calculator

Tips: Enter horsepower in hp, weight in pounds, and the appropriate constant. The default constant (0.000023) works for most passenger cars. Race cars may use lower constants (0.000018-0.000020).

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: It provides a theoretical maximum speed. Actual speed depends on gearing, traction, and other factors.

Q2: What's a typical constant value?
A: Most cars use 0.000023. Streamlined vehicles may use 0.000018-0.000020.

Q3: Does this account for transmission losses?
A: No, the calculation assumes all horsepower reaches the wheels. Subtract 15-20% for drivetrain losses.

Q4: Why the cube root relationship?
A: Aerodynamic drag increases with the square of speed, while power needed increases with the cube of speed.

Q5: Can this predict acceleration?
A: No, this only estimates top speed. Acceleration depends on torque curve and gearing.