1. What is a Quarter Mile ET Calculator?

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

Purpose: It helps automotive enthusiasts and racers predict their vehicle's performance in a straight-line drag race.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula approximates the relationship between power-to-weight ratio and quarter-mile performance, with the cube root accounting for non-linear acceleration.

3. Importance of Quarter Mile Calculation

Details: Quarter-mile time is a standard performance metric that helps compare vehicles and estimate the impact of modifications.

4. Using the Calculator

Tips: Enter the vehicle's curb weight 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 rough estimate. Actual performance depends on traction, gearing, aerodynamics, and driver skill.

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: No, add your weight to the vehicle's curb weight for more accurate results.

Q4: What's a good quarter mile time?
A: Times vary widely: 14-15s is quick for street cars, under 12s is very fast, and under 10s is professional drag racing territory.

Q5: Can I calculate trap speed too?
A: Yes, trap speed (mph) can be estimated with: \( \frac{234}{ET} \times HP^{0.288} \)