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Wallace Equation:
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The Wallace 1/8 Mile Equation is a mathematical formula used to estimate the elapsed time (ET) for a vehicle to complete a 1/8 mile drag race. It calculates performance based on the vehicle's weight and horsepower.
The calculator uses the Wallace equation:
Where:
Explanation: The equation demonstrates the cubic relationship between power-to-weight ratio and elapsed time, showing how small changes in either weight or horsepower can significantly affect performance.
Details: Accurate ET estimation helps racers predict vehicle performance, optimize modifications, and set realistic expectations for drag racing events. It's particularly useful for comparing different vehicle setups.
Tips: Enter vehicle weight in pounds and engine horsepower. Use actual measured horsepower if available for best accuracy. All values must be positive numbers.
Q1: How accurate is the Wallace equation?
A: The Wallace equation provides a good estimate for most vehicles but actual performance may vary due to traction, aerodynamics, transmission efficiency, and driver skill.
Q2: What is a good 1/8 mile ET?
A: ETs vary by vehicle type: Street cars typically run 8-10 seconds, performance cars 6-8 seconds, and professional dragsters 4-6 seconds.
Q3: Should I use curb weight or race weight?
A: For most accurate results, use race weight which includes driver, fuel, and any additional equipment carried during the run.
Q4: Does this work for all types of vehicles?
A: The equation works best for rear-wheel drive vehicles with good traction. Front-wheel drive and all-wheel drive vehicles may show different results due to drivetrain losses.
Q5: Can I use this for 1/4 mile estimation?
A: While primarily for 1/8 mile, you can roughly estimate 1/4 mile times by multiplying the 1/8 mile ET by approximately 1.55-1.57.