The Sonic and 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 42# and these are 72#. We now sell our custom valve spring tool to make installation that much easier!
This item comes in two different configurations:
-Valve Springs only
-Valve Springs & Titanium Retainers
About our Titanium Retainers:
August 2022 update: We now have the option to include our ZZP valve spring compressor tool with the purchase of your springs/retainers. Purchasing with the springs saves you $5 off the tool.