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Torque Formula:
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The Engine Torque Calculation Formula calculates torque from horsepower and RPM using the fundamental relationship between these three important engine performance parameters. This formula is widely used in automotive engineering and mechanical applications.
The calculator uses the torque formula:
Where:
Explanation: The constant 5252 comes from the relationship between horsepower, torque, and RPM, where 1 horsepower is defined as 550 foot-pounds per second and there are 5252 radians in one revolution at RPM speed.
Details: Torque calculation is essential for understanding engine performance, vehicle acceleration, towing capacity, and overall mechanical efficiency. It helps engineers design optimal gear ratios and transmission systems.
Tips: Enter horsepower and RPM values. Both values must be positive numbers. The calculator will compute the corresponding torque in pound-feet (lb-ft).
Q1: Why is the constant 5252 used in the formula?
A: The constant 5252 comes from unit conversions where 1 HP = 550 ft-lb/sec and there are 5252 radians per minute at 1 RPM, making the math work out perfectly.
Q2: What is the difference between torque and horsepower?
A: Torque is a measure of rotational force, while horsepower is a measure of work done over time. Horsepower = (Torque × RPM) / 5252.
Q3: At what RPM does torque equal horsepower?
A: Torque and horsepower are numerically equal at 5252 RPM, which is why this RPM is often marked on dyno charts.
Q4: Can this formula be used for electric motors?
A: Yes, the same fundamental relationship applies to electric motors, though the torque characteristics may differ from internal combustion engines.
Q5: How does gear ratio affect torque?
A: Gear ratios multiply torque - lower gears provide more torque multiplication at the expense of speed, while higher gears provide less torque multiplication but higher speed.