07 The distance between the rocker’s fulcrum (pivot point), and the tip where it contacts the top of the valve stem doesn’t change. The only way to adjust the rocker ratio is to change the distance between the end of the pushrod and the fulcrum. Increasing the rocker ratio is a good way to gain power, because it increases total valve lift without significantly affecting duration. This can help increase airflow, while still providing snappy throttle response. Just be careful to check piston to valve clearance whenever changing the rocker ratio, because the increased lift puts the valves closer to the piston tops. Also, notice how the fulcrum barrel of these high-ratio rockers had to be clearanced for the pushrod, to make sure it wouldn’t touch at maximum valve lift. Increasing the rocker ratio increases valvetrain complexity.