the certified calibration is on the speedometer and as far as i know its a more accurate speedometer than the factory one so the pigs, i mean police officers
can know "exactly" their speed and yours, there are many other little things they did to them too, just depends on where its from, i just found out mine has a block heater as well as all the other stuff, its nice only having to use one key and not having to reach over to the glove box to pop the trunk, i'd say definately buy one if you can find one
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88 Notch, 3.73's, Ported E7's, Explorer int. w/ ported lower, pulleys, 1.7RR's, BBK headers, off-road H-pipe, flowmasters, subframe connectors, 65mm TB, shift kit, March ram air ,MSD coil, U/L control arms, 155lph fuel pump, cheap 2800 stall, Crane Adj.FPR, best 1/4--> 13.77@101.35