Now you can fine tune your Turbo Actuator to the exact needs of your engine with this complete tuning kit. Your valve tuning kit you will find four springs and the associated spring retainer. The strongest spring is the red, followed by the blue, yellow and finally the green which is the weakest. We normally supply our actuators, unless requested differently, with a spring that will match the tension of the manufacturer’s original fitment valve. However, as many owners undertake tuning modifications some may wish to re-tune the actuator characteristics to suit a given application. Note: Serious or fatal damage may occur to the engine and associated components if this product is incorrectly matched to the individual engine requirements. Forge Motorsport nor any of it’s Authorised Distributors can assume any responsibility for any adverse effects resulting from the installation of this product Please select from the options above if you require this kit for a piston actuator or a diaphragm actuator. The 048 actuators are those with a big body, the 049 actuators are those with a standard size body. These kits are NOT suitable for our Diesel actuator for Garrett VNT turbos Valve Spring color coding: Green - 5-10 PSI, Yellow - 10-14 PSI, Blue - 14-18 PSI, Red - 19-23 PSI. *The above figures are estimates only and should only be considered as a guideline*