Using aftermarket rockers can pose a clearance problem when they are used with stock valve covers. This is especially true with high-ratio rockers, or shaft-mounted rocker systems. In the past the solution for this problem meant the purchase of expensive tall valve covers but that’s no longer a problem.
Street and Performance Electronics has developed a solution that delivers a high-tech look while maintaining affordability and ease of installation with their new Spacer-Max valve cover riser. They are available in three sizes for specific clearance requirements. The 1/2 “. 3/4" and 1” risers are CNC machined from T-6061 billet aluminum and tumble finished for a high quality high-tech appearance.
The 1/2” kit accommodates most clearance requirements for the street and strip enthusiast, and the 3/4" and 1” kit is designed for the all out serious racer. Spacer-Max kits come with everything that’s required for installation including extra O-ring gaskets to replace any that show excessive wear on the original valve covers as well as all other hardware for installation.
Current applications cover all the new GM LS1, LS2, LS6, ZO6 and 1999-2005 GEN III VORTEC truck engines, with many more applications to come.

This picture denotes the height of the aftermarket rockers when installed. You will see that the adjusting nuts are clearly an obstruction for the valve covers.

In this picture, you can see that when the cover is partially installed there is a gap between the valve cover and the cylinder head.

This picture shows the gap issue fixed by installing the Spacer-Max valve cover spacer, cleanly and without major cost.