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Quarter Mile ET Formula:
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The Quarter Mile ET (Elapsed Time) Calculator estimates the time it takes for a vehicle to complete a quarter mile (402 meters) drag race based on horsepower and weight. This is a fundamental performance metric in automotive racing and tuning.
The calculator uses the quarter mile ET formula:
Where:
Explanation: The formula calculates the cube root of the power-to-weight ratio (HP/Weight) and divides 1350 by this value to estimate quarter mile elapsed time.
Details: Quarter mile time is a standard performance measurement in drag racing that indicates a vehicle's acceleration capability. Lower times indicate better performance, with professional dragsters achieving times under 5 seconds.
Tips: Enter horsepower and vehicle weight in pounds. Use actual measured horsepower if available (not manufacturer's claimed figures). Include driver weight in total weight for more accurate results.
Q1: How accurate is this calculator?
A: This provides a theoretical estimate. Actual times vary based on traction, transmission, aerodynamics, and driving skill. It's best used for comparison purposes.
Q2: What is a good quarter mile time?
A: Under 12 seconds is considered fast for production cars. Under 10 seconds is extremely fast, while professional dragsters run under 5 seconds.
Q3: Does this account for drivetrain losses?
A: No, this uses engine horsepower. For wheel horsepower (which accounts for drivetrain losses), multiply the result by approximately 1.15 for rear-wheel drive vehicles.
Q4: Can I use this for motorcycles?
A: Yes, the formula works for any vehicle, but motorcycle times may differ due to different power delivery and traction characteristics.
Q5: What factors affect quarter mile time besides HP and weight?
A: Traction, gearing, aerodynamics, tire type, launch technique, and weather conditions all significantly impact actual quarter mile performance.