I'm setting up the four corner idle adjustment mixture screws on my Holley carburetor. This holley carburetor has four corner idle adjustment and I'm going to walk through setting it up step by step. All you really need to do this is a vacuum gauge and a small screw driver. Innova Vacuum Gauge: As an Amazon Affiliate I earn from qualifying purchases. Don't Forget to Subscribe! Don't forget to check us out on Instagram: All videos are for entertainment purposes only. Attempt these projects at your own risk! If you do, make sure you follow all manufacturers instructions!