Upsizing your truck's wheel and fire package for hunting season, or swapping in a new gear ratio, effectively changes your speedometer reading. Taller tires, for example, will deliver a lower speedometer reading than you are actually traveling. One solution is to change the speedometer gear in your transmission. What a bother. Another is to install the Intellitronix GPS Digital Speedometer. This nifty unit features a 10,000 rpm tach, voltmeter and 360-degree compass, and relies on GPS satellite signals to calculate travel speed. The supplied antenna receives a GPS signal to determine vehicle location at any given time. By calculating the time it takes to change location from one signal to the next, the speedometer's microprocessor is able to calculate your speed in tenths of a mile per hour.
Intellitronix, Dept. HM, 10800 Middle Ave., Building D-2, Elyria, OH 44035; 440/458-4858; www.intellitronix.com.