1. What is Horsepower from Torque and RPM?

Definition: This calculator computes horsepower (HP) using torque and revolutions per minute (RPM) values.

Purpose: It helps automotive engineers, mechanics, and enthusiasts determine engine power output based on torque measurements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Horsepower
• \( T \) — Torque in pound-feet (lb-ft)
• \( RPM \) — Revolutions per minute
• 5252 — Conversion constant (derived from the relationship between HP, torque, and RPM)

Explanation: Horsepower is calculated by multiplying torque by RPM and dividing by the constant 5252, which comes from the definition of horsepower.

3. Importance of Horsepower Calculation

Details: Horsepower is a crucial measurement for understanding engine performance, comparing different engines, and making tuning decisions.

4. Using the Calculator

Tips: Enter torque in lb-ft and engine speed in RPM. Both values must be greater than zero for accurate calculations.

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 5252 used?
A: 5252 is derived from the definition of horsepower (1 HP = 550 ft-lb/sec) and unit conversions between minutes and seconds.

Q2: At what RPM does torque equal horsepower?
A: Torque and horsepower values are equal at 5252 RPM due to the formula's constant.

Q3: Can I use this for electric motors?
A: Yes, the formula works for any rotating machinery where you can measure torque and RPM.

Q4: What's a typical torque value for a car engine?
A: Production car engines typically produce 100-400 lb-ft of torque, depending on size and design.

Q5: How does this relate to wheel horsepower?
A: This calculates engine horsepower. Wheel horsepower is typically 15-20% less due to drivetrain losses.