1. What is the Quarter Mile Time Equation?

The quarter mile time equation estimates a vehicle's elapsed time (ET) for a quarter mile drag race based on its weight and horsepower. This provides a theoretical performance benchmark for comparing vehicles.

2. How Does the Calculator Work?

The calculator uses the quarter mile time equation:

Where:

• \( Weight \) — Vehicle weight in pounds (lbs)
• \( HP \) — Engine horsepower (hp)
• 6.29 — Empirical constant for quarter mile calculation

Explanation: The equation shows that quarter mile time is proportional to the cube root of the weight-to-power ratio. This means doubling horsepower doesn't halve the time, but reduces it by about 20%.

3. Importance of Quarter Mile Time

Details: Quarter mile time is a standard performance metric in motorsports. It helps compare vehicle acceleration capabilities and is used by enthusiasts to evaluate modifications.

4. Using the Calculator

Tips: Enter vehicle weight in lbs and horsepower in hp. Both values must be positive numbers. The result is a theoretical estimate that doesn't account for traction, gearing, or driver skill.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: It provides a theoretical estimate. Real-world times vary due to traction, aerodynamics, transmission efficiency, and launch technique.

Q2: What's a good quarter mile time?
A: Street cars typically run 12-15 seconds. Performance cars run 10-12 seconds. Under 10 seconds requires specialized drag vehicles.

Q3: Does this account for drivetrain loss?
A: No, input wheel horsepower for more accurate results. Otherwise, the calculation assumes engine horsepower equals power at the wheels.

Q4: Why use the cube root in the formula?
A: The cube root relationship accounts for the non-linear effect of power-to-weight ratio on acceleration time.

Q5: Can I use this for motorcycles?
A: Yes, but motorcycle times may differ more due to weight transfer and rider skill playing a larger role.