Most of the web top speed calculators use engine (maximum rev), transmission (gear ratios) and tire (sizes) data to calculate a so called “theoretical maximum speed”. Although its original purpose was to compare the output of steam engines with the power of horses (hence its name), it has since been adopted as a unit of measurement for all sorts of engines used to power things such as vehicles, lawn mowers, boats, chainsaw, and airplanes. Enter your values: Torque: Pound-Foot Speed: Revolution Per Minute Result: Rotating Horsepower: Horsepower: Calculate Torque from Horsepower. Without knowing any more we can't calculate things like instantaneous speed or the maximum speed. Step 3: Multiply the torque value by the speed values of the engine. Torque is a rotational force generated by the electrical system, whereas, the horsepower is an imperial unit of power equal to 745.7 watts. You will be using the formula (RPM x T)/5252=HP, where RPM is the engine speed, T is the torque, and 5,252 is radians per second. A car's top speed is affected by many things. Intro. ¼ Mile Horsepower Calculator: MPH: Weight : HP : Enter the MPH and Weight and Click on Calculate... HP = Weight * (MPH / 234) ^3 Calculate Speed from Horsepower. Higher temperature, humidity or altitude will lower power output and decrease top speed. Horsepower. You can calculate the average speed using [math] speed = \frac{distance}{time \:\:taken}[/math]. The stock 93 RX-7 was rated at 255 HP at the flywheel and had a top speed of 158. Step 2: In the owner’s manual, look up the engine’s speed values. This calculator estimates your top speed when horsepower is added. Torque - Horsepower (hp) conversion is a method of converting one unit from other and vice versa. Horsepower is a unit of measurement of power developed by engineer James Watt in the late 18 th century. Enter your search terms Submit search form : Web: Calculate Rotating Horsepower. Tyre Circumference = 1992.71 mm 1st Gear = 57.44 km/h - 35.61 mph 2nd Gear = 84.24 km/h - 52.23 mph 3rd Gear = 108.31 km/h - 67.16 mph 4th Gear = 189.55 km/h - 117.52 mph