Wallace ET Calculator 1/8

1/8-Mile Elapsed Time Formula:

\[ ET = \left(\frac{W}{HP}\right)^{\frac{1}{3}} \times 4.025 \]

1/8-Mile Elapsed Time (s):

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1. What is the Wallace ET Calculator 1/8?

Definition: This calculator estimates 1/8-mile elapsed time (ET) for drag racing based on vehicle weight and horsepower.

Purpose: It helps racers and performance enthusiasts predict quarter-mile performance times.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ ET = \left(\frac{W}{HP}\right)^{\frac{1}{3}} \times 4.025 \]

Where:

\( ET \) — 1/8-mile elapsed time (seconds)
\( W \) — Vehicle weight (pounds)
\( HP \) — Engine horsepower

Explanation: The formula calculates theoretical performance based on power-to-weight ratio, with the cube root relationship showing diminishing returns from added power.

3. Importance of 1/8-Mile ET Calculation

Details: 1/8-mile times are commonly used in drag racing, especially at smaller tracks, and can predict quarter-mile performance.

4. Using the Calculator

Tips: Enter vehicle weight in pounds and engine horsepower. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculator?
A: It provides theoretical ET based on power-to-weight ratio. Actual times may vary due to traction, aerodynamics, and other factors.

Q2: Should I use flywheel or wheel horsepower?
A: For most accurate results, use wheel horsepower (measured at the wheels on a dyno).

Q3: Does this include driver weight?
A: The weight should include vehicle + driver + fuel + any other significant weight.

Q4: Can I use this for quarter-mile estimation?
A: While related, 1/8-mile times don't directly convert to 1/4-mile. Use a dedicated 1/4-mile calculator for that.

Q5: Why 4.025 as the multiplier?
A: This empirical constant was derived from analysis of thousands of drag racing runs by Wallace Racing.