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Wallace Formula:
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The Wallace Racing HP formula estimates horsepower based on elapsed time (ET) and vehicle weight. This empirical formula is commonly used in drag racing to approximate engine power output from quarter-mile performance data.
The calculator uses the Wallace formula:
Where:
Explanation: The formula establishes a cubic relationship between horsepower and the product of elapsed time and weight, providing a quick estimate of engine power based on drag strip performance.
Details: Accurate horsepower estimation is crucial for performance tuning, vehicle classification in racing categories, and comparing engine modifications. It helps racers understand the relationship between weight reduction and performance gains.
Tips: Enter quarter-mile elapsed time in seconds and vehicle weight in pounds. Both values must be positive numbers. The calculator will compute the estimated horsepower output.
Q1: How accurate is the Wallace formula?
A: The formula provides a reasonable estimate for most street and strip applications, but actual horsepower may vary due to traction, weather conditions, and drivetrain efficiency.
Q2: What type of ET should I use?
A: Use quarter-mile elapsed time measured under consistent conditions. The time should be from a complete pass with good traction.
Q3: Should I use race weight or curb weight?
A: Use race weight including driver, fuel, and all equipment as it would be during the actual run for most accurate results.
Q4: Are there limitations to this formula?
A: The formula works best for vehicles with good traction and consistent performance. It may be less accurate for extremely high or low horsepower applications.
Q5: Can this be used for different racing distances?
A: The formula is specifically calibrated for quarter-mile times. Using eighth-mile or other distance times will not provide accurate results.