Speedometer, bigger tires, VSS pulses, Didn't know quite where to put this Options

[Fastbird]

I see a lot of talk about the speedo being off with moving to bigger wheels and not running a low profile tire in order to maintain the overall factory wheel/tire diameter. To some it may be no big deal, but I'd rather know for sure how fast I'm moving.

I didn't see it mentioned yet which is a little surprising, but Dakota Digital makes a nifty little piece called the SGI-5 Speedometer Recalibrator. SEEN HERE. It's relatively inexpensive and isn't something too difficult to install so long as you can correctly identify your VSS wiring in the correct location.

Now, something that is dependent on this working is how many pulses per mile the Celica VSS gives off. Anyone know this information???

Provided it works, it's fairly simple to recalibrate the speedo for a larger diameter wheel/tire combo. Just have a look at the Miata Tire Size Calculator and figure out what your correction factor is, and calibrate the SGI-5 for the new setup.