Originally posted by More&Faster
btw i think my speedometer is dead on accurate as well. that is assuming that my tach is accurate as well, but assuming that....you can just calculate your speed. dont even look at the speedo, just find out what your final drive ratio is and multiply it by the rpm shown on the tach.
Sorry pal but the tach isn't really that accurate. It can vary by as much as 500 RPM. How do you know if your guages are accurate? Have you checked your speedometer reading against something like a GPS or a G-tech? Not to say that either is perfect but they're both useful for calibration purposes.