ECS Supercharging systems are designed to allow the user to have the ultimate control of the boost output from the kit based on their application, elevation, fuel available, etc. Our restrictor plate design allows you to fine tune boost to really dial in your vehicle for the street and track along with compensating for changing track conditions with the change of an plate and air filter removal. **Tuning changes required for any increase in boost levels** ECS Large Restrictor plate for C5, C6 and Camaro ECS Supercharging systems. These are used to regulate boost levels. For use with ECS supercharging systems and corresponding air filters. Inlet inside diameter is 2.95″. (LS1,LS6,LS2,LS3) Recommended used with Methanol Injection or Race Gas.