1. What is a Power to Weight 1/4 Mile Calculator?

Definition: This calculator estimates a vehicle's horsepower based on its weight and 1/4 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)
• \( ET \) — 1/4 mile elapsed time (seconds)

Explanation: The formula relates power-to-weight ratio to acceleration performance over a quarter mile distance.

3. Importance of Power-to-Weight Calculation

Details: This calculation helps compare vehicle performance potential and estimate engine power modifications.

4. Using the Calculator

Tips: Enter vehicle weight in pounds and 1/4 mile time in seconds. Both 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: What's the significance of 5.825 in the formula?
A: This is an empirical constant derived from drag racing data that relates ET to power-to-weight ratio.

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

Q4: Does this work for all vehicle types?
A: It works best for rear-wheel drive cars with good traction. FWD/AWD may show different results.

Q5: Can I use 1/8 mile times?
A: No, this formula is specifically calibrated for 1/4 mile elapsed times.