Quarter Mile Time Calculator

Quarter Mile Time Formula:

\[ ET = \left(\frac{W}{HP}\right)^{\frac{1}{3}} \times 5.825 \]

Quarter Mile Time (seconds):

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1. What is a Quarter Mile Time Calculator?

Definition: This calculator estimates a vehicle's elapsed time (ET) for a quarter-mile drag race based on weight and horsepower.

Purpose: It helps automotive enthusiasts and racers predict performance without actual track testing.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ ET = \left(\frac{W}{HP}\right)^{\frac{1}{3}} \times 5.825 \]

Where:

\( ET \) — Elapsed Time (seconds)
\( W \) — Vehicle weight (pounds)
\( HP \) — Engine horsepower

Explanation: The cube root of the weight-to-power ratio is multiplied by an empirical constant (5.825) that accounts for typical acceleration patterns.

3. Importance of Quarter Mile Time

Details: Quarter mile time is a standard performance metric that reflects a vehicle's acceleration capability and power-to-weight ratio.

4. Using the Calculator

Tips: Enter the vehicle's curb weight (including driver) in pounds and the engine's horsepower. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: It provides a reasonable estimate but doesn't account for traction, gearing, or aerodynamics. Actual times may vary by ±0.5 seconds.

Q2: Should I use wheel horsepower or crank horsepower?
A: For most accurate results, use wheel horsepower (measured at the wheels).

Q3: Does this include driver weight?
A: The calculation uses total moving weight - include the driver's weight in your input.

Q4: What's a good quarter mile time?
A: Street cars typically run 13-16 seconds. Performance cars run 10-12 seconds. Under 10 seconds requires specialized drag vehicles.

Q5: Can I calculate horsepower from a known quarter mile time?
A: Yes, rearrange the formula: \( HP = W / (ET / 5.825)^3 \)