GM / Dodge Ratio Adapter, Select Slow Down Percent
54RA. This GM / Dodge / ratio adapter will slow your speedometer reading down. Made for low rear end ratios with short tires. Offset for clearance reasons. If your GM speedometer reads too fast with 15 and 45 teeth gears then you need this part. This part will slow down your speedometer reading.
Use -37.5% to convert Kilometers to MPH.