1. What is Power To Weight Ratio?

The Power to Weight Ratio (PWR) is a measurement of a vehicle's horsepower relative to its weight. It's a key indicator of a car's performance potential, with higher ratios generally indicating better acceleration and performance.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( PWR \) — Power to weight ratio (hp/lb)
• \( HP \) — Horsepower (hp)
• \( Weight \) — Vehicle weight (lb)

Explanation: The formula calculates how much power is available for each pound of vehicle weight, which directly affects acceleration and performance.

3. Importance of PWR Calculation

Details: PWR is crucial for comparing vehicle performance potential. Higher PWR means better acceleration and often better overall performance, though other factors like gearing and aerodynamics also play important roles.

4. Using the Calculator

Tips: Enter horsepower in hp and weight in pounds. Both values must be greater than zero. For metric units (kW and kg), convert first (1 hp = 0.7457 kW, 1 lb = 0.4536 kg).

5. Frequently Asked Questions (FAQ)

Q1: What is a good power to weight ratio?
A: For street cars, 0.06-0.1 hp/lb is good. Performance cars are 0.1-0.15 hp/lb. Racing cars can exceed 0.2 hp/lb.

Q2: How does PWR affect acceleration?
A: Higher PWR generally means faster acceleration, though traction, gearing, and aerodynamics also significantly impact actual performance.

Q3: Should I use curb weight or gross weight?
A: For performance comparisons, use curb weight (empty vehicle weight). For real-world estimates, you might add driver/passenger weight.

Q4: How does PWR compare between different units?
A: 1 hp/lb ≈ 2.205 hp/kg. The same ratio in metric would be kW/kg (1 hp/lb ≈ 1.646 kW/kg).

Q5: Why is PWR more important than raw horsepower?
A: A lighter car with less power can outperform a heavier car with more power if it has a better PWR.