Hey, the speedo doesn't work at all. I have tried "000" and that keeps the speedo at 50... but that is just verification that it's installed correctly. I have tried "100" nothing happens. I have tried all the way up to "999". I guess what I am asking is what would I need to calculate to get the right settings? I already tried calculating by gears and by tire size. Surely someone must have done this before?
This is what you do. You need 2 numbers to divide to input it into the speed cal.
1. Reset your trip meter. Figure out the actual miles driven, you can use the freeway mile markers or gps to get this number. Lets say you drive 5
actual miles as an example.
2. Record the number of miles your trip meter registered after going the 5
actual miles. Lets say for example, your trip meter read 7
miles (assuming you went with a numerically higher gear ie 3.73 or 4.10, in any case your trip meter will read higher than your actual miles driven.)
3. Divide the two numbers 5
4. Therefore, set the speed cal to 071.
The speed cal dial is set as a ratio, so, your correction factor will always be below 100 when going from a numerically lower gear to a higher one.
Note: When you calculate it this way, you don't need to take tire size into account. It is already accounted for. Also, when you make your calculations, just round your answer off, rounding will make a negligible difference.
Hope this helps.
1998 GT- 5 speed. Crystal White. C&L CAI, 80mm MAF, TrickFlow 75mm throttle body, TrickFlow Upper intake plenum, Underdrive pullies, BBK catted X-pipe, 4.10 gears, limited slip diff with carbon fiber discs, moser 31 spline axles. MM FLSFCs, Screaming demon coil packs, Ford Racing 9mm wires, SR lowering springs, 95 cobra R rims, black, machined lip 18X9's in front, 18X10's in rear, Bullitt style pedals, SVE race seats.