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TechnologyGenerated accuracy model review: 2026-05-06
Engine Horsepower accuracy and testing
This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.
Formula source
- The universal formula for mechanical horsepower is: **HP = (Torque × RPM) / 5252** The constant 5252 comes from converting units (33,000 ft-lb/min / 2π radians).
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Torque: 300 ft-lb
- RPM: 5,500 rev/min
Expected outputs
- Horsepower: 314 HP
Known limitations
- This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
- Use the result as a planning estimate unless the calculator page states a stricter purpose.
Assumptions
- Torque is entered in pound-feet and RPM is entered as engine speed in revolutions per minute.
- This calculator uses the standard 5252 constant for mechanical horsepower in imperial units.
- Negative torque or RPM values are invalid for this use case.
Unit handling
- Torque accepts values in ft-lb.
- RPM accepts values in rev/min.
- Horsepower is displayed in HP.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current engine-horsepower-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for Engine Horsepower.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.