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Gear Speed and Tire Size app for iPhone and iPad


4.6 ( 3936 ratings )
Utilities Productivity Sports
Developer: Scott Galaba
1.99 USD
Current version: 3.9.29, last update: 1 year ago
First release : 26 Oct 2015
App size: 7.73 Mb

The Gear Speed and Tire Size Calculator app is for comparing different tire and wheel combinations to transmission gears and differential ratios. Preload gear ratios are provide and gear speeds 4-8 are selectable to tailor the output results to the transmission (4-speed, 5-speed, 6-speed, 7-speed, 8-speed).

The Gear Speed Graph is interactive and allows one to compare results when hovering over / selecting a line graph point(s) to display the Comparison Graph Results Panel. The Gear Speed Graph also allows one to compare, hide, or show a given gear speed line graph by selecting the corresponding legend indicator to toggle the display of the selected line graph.

Calculations can be printed or saved into a PDF by selecting Share PDF Results.

Multitasking / Slide Over / Split View support is included for the latest iPads.

This App includes three (3) different calculators:

(1) Gear Speed Calculator - For calculating the speed in MPH or KPH for a given tire size, up to eight (8-speed) transmission gear ratios and differential ratio combination. The results appear in both an interactive Gear Speed Graph and Gear Speed Results Table (table not available for 3.5 inch display but does appear in the Share PDF Results feature). RPM Data Points are adjustable, allowing for further tailoring of the Gear Speed Graph and Results, to very specific RPM ranges, or to expanded the ranges beyond 9000 rpm.

(2) Tire Size Calculator - For comparing the original equipment tire size (Rim in inches) to alternate after market tire sizes.

(3) TMX Tire Size Calculator - For comparing the original equipment tire size (Rim in millimeters) to alternate after market tire sizes.