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Quarter-mile ET Equation:
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The Wallace Racing Calculator estimates quarter-mile elapsed time (ET) based on vehicle weight and horsepower. This empirical formula is widely used in drag racing to predict vehicle performance and compare different setups.
The calculator uses the Wallace racing equation:
Where:
Explanation: The equation demonstrates that ET is proportional to the cube root of the weight-to-power ratio, showing how power-to-weight ratio significantly impacts acceleration performance.
Details: Quarter-mile elapsed time is a standard performance metric in drag racing. Accurate ET prediction helps racers optimize their vehicles, select appropriate classes, and set realistic performance goals.
Tips: Enter vehicle weight in pounds and engine horsepower. Use actual measured values for best accuracy. All values must be valid (weight > 0, horsepower > 0).
Q1: How accurate is the Wallace racing calculator?
A: The calculator provides a good estimate for most street and strip vehicles, but actual performance may vary due to traction, gearing, and driving technique.
Q2: What is considered a good quarter-mile ET?
A: For street cars, 12-14 seconds is good performance. Professional drag cars can run 6-7 seconds, while supercars typically run 10-12 seconds.
Q3: Should I use wheel horsepower or engine horsepower?
A: For most accurate results, use wheel horsepower as this represents the actual power delivered to the ground.
Q4: Does this account for driver weight and fuel?
A: No, the calculator uses vehicle weight only. For race calculations, include driver weight and half-tank of fuel for accurate results.
Q5: Can this be used for different racing surfaces?
A: The formula is optimized for prepared drag strips. Times may be slower on street surfaces due to reduced traction.