Racing Calculators ¼ Mile Horsepower Calculator         MPH Weight       HP       Enter the MPH and Weight and Click on Calculate... HP = Weight * (MPH / 234) ^3 ¼ Mile ET & MPH Calculator #1         Weight HP     ET MPH     Enter the Weight and HP and Click on Calculate twice... MPH = 234 * (HP / Weight) ^ .3333 ET = 1353 / MPH ¼ Mile ET & MPH Calculator #2     ET     MPH     Enter the ET or MPH and Click on Calculate... ET = 1353 / MPH MPH = 1353 / ET ¼ Mile ET & 1/8 Mile ET Conversions     ¼ Mile ET     1/8 Mile ET     Enter the ¼ Mile ET or the 1/8 Mile ET and Click on Calculate... ¼ Mile ET = (1/8 Mile ET + .22) / .655 1/8 Mile ET = (¼ Mile ET * .655) - .22 Engine Displacement Calculator         Bore Stroke # of Cylinders     Displacement     Enter the Bore in inches, the stroke in inches, the number of cylinders, and Click on Calculate... Displacement = (Bore / 2) ^2 * PI * Stroke * # of cylinders