1. What is the 1/8 Mile Horsepower Calculation?

The 1/8 mile horsepower calculation estimates engine power based on vehicle weight, speed, and elapsed time over an 1/8 mile distance. It's commonly used in drag racing to evaluate vehicle performance.

2. How Does the Calculator Work?

The calculator uses the 1/8 mile horsepower formula:

Where:

• \( Weight \) — Vehicle weight in pounds (lb)
• \( Speed \) — Trap speed in miles per hour (mph)
• \( ET \) — Elapsed time in seconds (s)
• 234 — Empirical constant for 1/8 mile calculations

Explanation: The formula accounts for the relationship between vehicle mass, acceleration, and speed over a fixed distance.

3. Importance of 1/8 Mile Performance

Details: 1/8 mile times are commonly used in drag racing as they require less space than 1/4 mile tracks while still providing meaningful performance data.

4. Using the Calculator

Tips: Enter vehicle weight in pounds, trap speed in mph, and elapsed time in seconds. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this horsepower calculation?
A: It provides a good estimate but actual dyno testing is more precise due to factors like drivetrain loss and traction.

Q2: Can I use this for 1/4 mile calculations?
A: No, this formula is specifically for 1/8 mile. Different constants are used for 1/4 mile calculations.

Q3: Should I use race weight or curb weight?
A: For most accurate results, use the vehicle's actual weight during the run including driver and fuel.

Q4: Why is speed more important than ET in this calculation?
A: Speed at the finish line better reflects power while ET is more affected by traction and launch technique.

Q5: What's a good 1/8 mile time for street cars?
A: Performance varies widely, but 8-9 seconds is good for modified street cars, while 7-8 seconds indicates high performance.