1. What is Horsepower to Weight Ratio?

Definition: This calculator determines the power-to-weight ratio by dividing the engine's horsepower by the vehicle's weight.

Purpose: It helps automotive enthusiasts and engineers evaluate a vehicle's performance potential, as higher ratios typically indicate better acceleration.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{HP/W} \) — Horsepower to weight ratio (HP per pound)
• \( \text{HP} \) — Engine horsepower
• \( \text{W} \) — Vehicle weight in pounds

Explanation: The ratio shows how much power is available to move each pound of vehicle weight.

3. Importance of HP/W Ratio

Details: This ratio is a key performance metric in automotive design, racing, and vehicle comparison. Higher ratios generally mean better acceleration.

4. Using the Calculator

Tips: Enter the engine's horsepower and the vehicle's curb weight in pounds. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a good HP/W ratio?
A: For street cars, 0.05-0.08 HP/lb is good. Performance cars range 0.08-0.12 HP/lb. Race cars often exceed 0.15 HP/lb.

Q2: How does this relate to acceleration?
A: Higher ratios generally mean faster acceleration, though traction, gearing, and aerodynamics also play roles.

Q3: Should I use gross or net horsepower?
A: Use the same measurement consistently for comparisons. Modern specs typically use SAE net horsepower.

Q4: What weight should I include?
A: For most accurate results, use curb weight (vehicle + fluids + full tank) plus driver/passenger weight.

Q5: How can I improve my HP/W ratio?
A: Either increase horsepower (engine modifications) or reduce weight (lightweight components).