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Quarter-Mile ET Equation:
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The Quarter-Mile ET Calculator estimates elapsed time for a vehicle to complete a quarter-mile drag race based on power-to-weight ratio. This calculation provides a theoretical performance benchmark for automotive enthusiasts and racers.
The calculator uses the quarter-mile equation:
Where:
Explanation: The equation demonstrates the cubic relationship between power-to-weight ratio and quarter-mile performance, where small changes in power or weight can significantly impact elapsed time.
Details: Power-to-weight ratio is a critical performance metric in automotive engineering. A lower ratio (more power per pound) typically results in better acceleration and faster quarter-mile times. This calculation helps enthusiasts compare vehicle performance potential and plan modifications.
Tips: Enter vehicle weight in pounds and engine horsepower. Use curb weight for most accurate results. All values must be valid (weight > 0, HP > 0). The result provides estimated quarter-mile elapsed time in seconds.
Q1: How accurate is this calculation?
A: This provides a theoretical estimate. Actual performance depends on traction, transmission, aerodynamics, driver skill, and environmental conditions.
Q2: Should I use wheel horsepower or engine horsepower?
A: For most accurate results, use wheel horsepower (measured at the wheels) as it accounts for drivetrain losses. Engine horsepower will give optimistic results.
Q3: What is a good quarter-mile time?
A: Times vary by vehicle type: 14+ seconds (economy cars), 12-14 seconds (sports cars), 10-12 seconds (high-performance), sub-10 seconds (dedicated race cars).
Q4: Does this account for different drivetrains?
A: No, this is a basic calculation. Front-wheel drive, rear-wheel drive, and all-wheel drive vehicles will perform differently even with identical power-to-weight ratios.
Q5: Can I use this for motorcycles?
A: Yes, though motorcycle aerodynamics and traction characteristics differ significantly from cars, so results may vary.