Alright, back to the magic formula. I had my power valve numbers incorrect in the above. Documented the changes here.
Holley Carburetor, Model 4160, 390 cfm, 4-Barrel, Electric Choke, Single Inlet, Dichromate
Started with
• Offenhauser intake, unheated
• Power valve 10.5
• Main jets 54 (.054" diameter)
• 35 accelerator
• Secondary jets 59
• Set timing to 18BTDC initial
• Cylinders 1&2 plugs are really fouled, 3-6 dark brown. Believe the unheated intake had something to do with the inconsistently.
• Great performance off the line
Next change
• Clifford intake, water heated
• Power valve 9.5
• Main jets 52 (.053" diameter)
• Cylinders 1-6 darkish brown but at least consistent
• Bogs down off the line
Final change
• Power valve 10.5
• Main jets 51.2 (.051" diameter)
• Cylinders 1-6 light brown and consistent
• Great performance off the line!
