Originally Posted by SteveP

The LOW/HIGH and A/B blocks are made to give us an option to adjust the angle of the front hinge pins to change the arm angle. This is referred to as anti-dive in correct terms. The best option for a road car is to reduce the arm angle by installing the high mount for the upper arms, and the "B" block below, you're essentially increasing anti-dive by two-degrees. This is more appropriate for a car racing on asphalt.