Shift RPM for the iPhone and iPad will determine the ideal RPM at which you should shift gears for maximum acceleration. It does this by creating a graph of the torque at the rear wheels in each of the transmission gears. The point at which these curves overlap is the point at which there is more torque available in the next gear and when you should shift.
To create this graph, you need to supply the engine torque or power curve (Shift RPM automatically calculates the other data point for a given RPM). We’ve included the information for 20 vehicle/engines (including BMW, Honda, Mazda, plus race cars and motorcycles from Honda, Kawasaki, Suzuki and Yamaha), so if you don’t have your exact engine, you can choose something similar to start. You’ll also need the gear ratio information along with the driven wheel tire size and final drive ( sometimes referred to as rear-end or ring&pinion) ratio.
Entering this information into the app is easy and fun. Spin the wheels to select gear ratios, or enter a numeric value using either the keypad or voice recognition.
The graph and analysis are created instantly so you can see the shift RPM, as well as the ideal speed ranges for each gear. You can change details like gear ratios, rear sprockets or tire size and see how that affects the speed in each gear.
You can organize and record different gear combinations used for different tracks, or see the effect a new engine rebuild has on the gears you would use.
With Shift RPM you’re not just limited to the graph shown on the screen -- you can create a PDF report showing the RPM analysis, speed range for each gear (along with the RPM drop as you shift), and the engine torque & power curve. You can print this report, or send it as an email attachment to anyone.