1. What is a HP to 1/8 Mile Calculator?

Definition: This calculator estimates a vehicle's 1/8-mile elapsed time (ET) based on its weight and engine horsepower.

Purpose: It helps automotive enthusiasts and racers predict quarter-mile performance from basic vehicle specifications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula approximates the relationship between power-to-weight ratio and acceleration performance.

3. Importance of 1/8-Mile Calculation

Details: 1/8-mile times are commonly used in drag racing and provide a good indicator of a vehicle's acceleration capabilities.

4. Using the Calculator

Tips: Enter the vehicle's curb weight (including driver) in pounds and the engine's horsepower. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: It provides a rough estimate. Actual performance depends on traction, gearing, aerodynamics, and other factors.

Q2: Can I use this for 1/4-mile times?
A: 1/4-mile times are typically about 1.56 times the 1/8-mile time for most vehicles.

Q3: Should I use wheel horsepower or engine horsepower?
A: For most accurate results, use wheel horsepower (typically 15-20% less than engine horsepower).

Q4: Does this include reaction time?
A: No, this calculates elapsed time only from when the vehicle starts moving.

Q5: What's a good 1/8-mile time?
A: Street cars typically run 9-11 seconds, while purpose-built drag cars can run under 6 seconds.