Quarter Mile Time & Trap Speed from Horsepower CalculatorUse the quarter mile calculator below to get a rough estimate of what quarter mile time a vehicle would run. Fill in the vehicles weight, and horsepower to get your approximate quarter mile time. Vehicle Weight With Driver :Vehicle Wheel Horsepower : Please note that this is an approximate figure based on almost perfect driving. Do not rely on this as 100% accurate. If you want to know your actual 1/4 mile time and trap speed, you will have to visit a track.