Holley Vacuum Secondary Tuning EXPLAINED | Holley Carb Secrets | Holley 1850 4160 4150

Today I&be showing you guys how the vacuum secondary system works on a holley carb. This particular carb is a holley 80457S vacuum secondary aluminum main body. This holley carb had a stuck accelerator pump and plugged air bleeds. It made it really hard to keep running so we had to take it off and swap it for a holley 1850. The 1850 is also a 600 cfm carb but it is a zinc body instead of aluminum. Today I&showing you guys how to tune the vacuum secondaries on a holley. Its not rocket science, and with a little bit of effort, you can get your vacuum secondary carb running like efi.