Learn how to tune a Holley type four-barrel carburetor, and see deep inside how they work, as I supertune my Red Duster for better road manners! I’ll take you inside the idle circuit, transfer slots, power valves, jetting, and accelerator pump tuning. I’ll show you how venturi size interacts with jet size. I’m doing it all with a 750 Brawler double pumper on my 360 Mopar. Moat of the tips here apply to 4160 and 4150 carburetors from Holley, Brawler, Demon, QFT, FST, and Proform. After I was done, I realized that I forgot to show you how accelerator pump cams work. Oh well! That’ll be a tip for next time. Thanks for watching.—D/F