1. What is the Quarter-Mile ET Equation?

The Quarter-Mile Elapsed Time (ET) equation estimates vehicle performance in a quarter-mile drag race based on weight and horsepower. This formula provides a theoretical elapsed time that helps racers and enthusiasts predict vehicle performance.

2. How Does the Calculator Work?

The calculator uses the quarter-mile ET equation:

Where:

• \( Weight \) — Vehicle weight in pounds (lb)
• \( HP \) — Engine horsepower (HP)
• \( 0.333 \) — Cube root exponent
• \( 5.825 \) — Empirical constant

Explanation: The equation calculates the cube root of the weight-to-power ratio and multiplies by a constant factor to estimate quarter-mile elapsed time.

3. Importance of ET Calculation

Details: Quarter-mile elapsed time is a standard performance metric in drag racing. Accurate ET estimation helps racers tune their vehicles, compare performance, and set realistic expectations for track performance.

4. Using the Calculator

Tips: Enter vehicle weight in pounds and engine horsepower. Both values must be positive numbers. The calculator provides an estimated quarter-mile elapsed time in seconds.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this ET calculation?
A: This provides a theoretical estimate. Actual ET can vary based on traction, aerodynamics, driver skill, and other factors.

Q2: What is considered a good quarter-mile time?
A: Times vary by vehicle type: 14+ seconds for average cars, 12-13 seconds for performance cars, under 10 seconds for dedicated race cars.

Q3: Does this account for drivetrain losses?
A: No, this uses raw horsepower. For wheel horsepower, results will be more accurate for actual performance.

Q4: Can I use this for motorcycles?
A: Yes, though motorcycle aerodynamics and weight distribution may affect actual performance differently.

Q5: What factors affect real-world ET besides weight and HP?
A: Traction, gearing, shift speed, aerodynamics, temperature, altitude, and track conditions all significantly impact actual quarter-mile times.