1. What is a Weight vs Horsepower Calculator?

Definition: This calculator estimates the horsepower needed to achieve a specific quarter-mile elapsed time (ET) based on vehicle weight.

Purpose: It helps automotive enthusiasts and racers understand the relationship between weight, horsepower, and quarter-mile performance.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Estimated horsepower
• \( W \) — Vehicle weight (pounds)
• \( ET \) — Quarter-mile elapsed time (seconds)

Explanation: The formula shows how horsepower requirements increase exponentially as desired ET decreases, and linearly with vehicle weight.

3. Importance of Weight vs Horsepower Calculation

Details: Understanding this relationship helps in vehicle tuning, performance planning, and setting realistic performance goals.

4. Using the Calculator

Tips: Enter the vehicle weight in pounds and desired quarter-mile time in seconds. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What does the 5.825 constant represent?
A: This empirical constant accounts for typical drag racing conditions and vehicle dynamics in the quarter-mile.

Q2: How accurate is this calculation?
A: It provides a good estimate but actual results vary based on traction, aerodynamics, and drivetrain efficiency.

Q3: Does this include driver weight?
A: Yes, the weight should include the vehicle plus driver and any additional load during the run.

Q4: What's a typical ET for street cars?
A: Performance cars: 12-14 seconds, Sports cars: 14-16 seconds, Average cars: 16+ seconds.

Q5: How can I improve my ET?
A: Either reduce weight, increase horsepower, or improve traction and launch technique.