Those are simply dials for the gauges. They have no impact, other than appearance, on your speedo. If you got the 180 version your speedo would be off by as much as it is now. If you get the 220 version they will be off by some factor and won't be programmed to display anything above 180. In short, you have to get something (SpeedoHealer or Yellow Box) to correct for the error in your speedometer.