Home
Back
Power-to-Weight Ratio Formula:
| From: | To: |
The Power-to-Weight Ratio (PWR) is a critical performance metric that measures the amount of power available per unit of weight. In automotive applications, it directly correlates with acceleration performance and is particularly important for 1/8 mile drag racing calculations.
The calculator uses the Power-to-Weight Ratio formula:
Where:
Explanation: Higher PWR values indicate better acceleration potential, as more power is available to move each pound of vehicle weight.
Details: The power-to-weight ratio is a key determinant of 1/8 mile acceleration times. Vehicles with higher PWR typically achieve faster elapsed times and higher trap speeds in drag racing competitions.
Tips: Enter horsepower in hp and vehicle weight in pounds. Both values must be positive numbers. The calculator will compute the power-to-weight ratio in hp per pound.
Q1: What is a good power-to-weight ratio for 1/8 mile racing?
A: Competitive ratios typically range from 0.08 to 0.15 hp/lb for street cars, while professional drag cars can exceed 0.30 hp/lb.
Q2: How does PWR affect 1/8 mile times?
A: Generally, each 0.01 increase in PWR can reduce 1/8 mile times by approximately 0.1-0.2 seconds, depending on traction and other factors.
Q3: Should I include driver weight in the calculation?
A: For accurate performance predictions, include the driver's weight plus any additional cargo or fuel weight beyond the standard vehicle weight.
Q4: Can PWR predict exact 1/8 mile times?
A: While PWR is a strong indicator, actual performance also depends on traction, aerodynamics, transmission efficiency, and launch technique.
Q5: How can I improve my vehicle's PWR?
A: Increase horsepower through engine modifications or reduce weight by removing non-essential components and using lightweight materials.