1. What is a HP from 1/8 Mile ET Calculator?

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

Purpose: It helps automotive enthusiasts and professionals estimate engine power without dyno testing.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula relates elapsed time to power-to-weight ratio, with 4.025 being an empirical constant.

3. Importance of HP Calculation

Details: Accurate horsepower estimation helps in vehicle tuning, performance comparison, and diagnosing engine issues.

4. Using the Calculator

Tips: Enter the vehicle weight in pounds and 1/8-mile elapsed time in seconds. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: It provides a rough estimate. Actual HP may vary due to traction, aerodynamics, and drivetrain losses.

Q2: Should I use curb weight or race weight?
A: Use the actual weight during the run (race weight) for most accurate results.

Q3: Can I use 1/4-mile times instead?
A: No, this formula is specifically calibrated for 1/8-mile times.

Q4: Why is weight such an important factor?
A: Acceleration depends on power-to-weight ratio, so heavier vehicles need more power for the same ET.

Q5: What's a good 1/8-mile ET for my car?
A: Performance varies, but stock family cars typically run 10-12 seconds, while dragsters can run under 5 seconds.