The Hot Rod Calculator allows easy, on the spot, calculations of how engine modifications and at track vehicle setup changes can effect power output and track performance. Easy to use formulas for the professional or novice will show you how engine changes like compression ratio and air fuel mixture affect your engine's power and torque outputs. At the track, see how things like gear ratio changes or weather conditions can affect your E.T. (accurate weather data required). Hot Rod Calculator - Street and Strip performance calculator for use by racers, engine builders and automotive enthusiasts. This is the chance to know up front how changes will translate into power and performance, so before you spend your time or money, use the Hot Rod Calc to get the answers. Pre-programmed formulas for engine building and track tuning. Quick reference guide with 100s of formulas included for ease of use. Easy to use, self contained, no additional computer or monitors required (accurate weather data required for some ET calculations) Hand held, take it anywhere, and includes protective Armadillo case at no additional charge. Universal for or use to do any mathematical calculations related to engine performance and vehicle E.T.