The Gen2 "LE2" Cruze comes with very light valve springs from the factory. Whenever you bump the rev limiter and/or boost the valve springs will start to float. This is bad for a few different reasons, it is hard on the valves/valve seats themselves, and it reduces power because the valves are not opening and closing properly like they should. When you install our ZZP valve springs, you will be able to rev the car out further and make power power at the top of the rev range. The stock valve springs are measured at 51# and these are 75#.
We recommend installation be performed with our LE2 valve spring tool kit, which can be found here.