#horsepower

Quarter-mile drag-strip maths as an API, computed locally and deterministically — the classic empirical estimates a racer, tuner or car enthusiast uses to relate a car's power and weight to its performance. The et endpoint gives the predicted elapsed time and trap speed from flywheel horsepower and race weight using the standard formulas — ET = 5.825 × (weight ÷ hp) raised to the one-third, trap speed = 234 × (hp ÷ weight) raised to the one-third — so a 3,000 lb car with 300 hp is predicted to run about 12.6 seconds at 109 mph, assuming a competent launch and decent traction. The horsepower endpoint runs it in reverse: because trap speed is set by power-to-weight and barely by the launch, hp ≈ weight × (trap ÷ 234) cubed is a popular way to estimate flywheel power straight off a timeslip. The power-to-weight endpoint gives the ratio that actually decides acceleration — in horsepower per pound, horsepower per ton and watts per kilogram, the cleanest cross-unit figure — with a performance class from commuter through hot hatch and supercar to hypercar, because a light 200 hp car can beat a heavy 400 hp one. Everything is computed locally and deterministically, so it is instant and private. Ideal for drag-racing and tuner apps, car-spec and comparison tools, automotive enthusiasts and motorsport dashboards. Pure local computation — no key, no third-party service, instant. Empirical estimates assuming a good launch and traction — not a timeslip. 3 compute endpoints. For aerodynamic drag use a drag API; for gearing use a gear-ratio API.

api.oanor.com/quartermile-api

Rotational and shaft-power maths as an API, computed locally and deterministically. The power endpoint relates mechanical power, torque and rotational speed — give any two of the power, the torque in newton-metres and the speed in rpm and it returns the third using P = T·ω with ω = 2πN/60, reporting the angular velocity and the power in watts, kilowatts, mechanical horsepower and metric horsepower (PS). The angular endpoint converts a rotational speed freely between rpm, radians per second, degrees per second and hertz (revolutions per second), and — given a radius — the tangential speed and centripetal acceleration at the rim. The units endpoint converts power across watts, kilowatts, mechanical horsepower (745.7 W), metric horsepower or PS (735.5 W), foot-pounds per second and BTU per hour. Everything is computed locally and deterministically, so it is instant and private. Ideal for automotive, motor, drivetrain, robotics and machinery app developers, engine and gearbox tools, and mechanical-engineering education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is mechanical shaft power; for bolt tightening torque use a torque API and for electrical power factor a power-factor API.

api.oanor.com/shaftpower-api