When revving your FSI engine higher than stock, you run into the problem of rocker arms falling off and breaking spring clips. This can cause severe damage to your engine. These Ferrea lifter shims will shorten the travel distance of the lifters and reducethe risk of breaking the rocker arms and lifters. The install in simple by just placing them below the hydraulic lifters.
Disclaimer: We recommend these only for race applications only. In engines with valve jobs, valve install height must be checked before installation to ensure that valves will remain closed with shims installed. If the valve job is cut too far into the head, valves will remain open at all times and engine will not run.
Sold as a complete set of 16.