Thread: vacuum advance question

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Please do not take my comments as being argumentative. I destroyed an engine with constant flooding from adjustments on the Holley Avenger I have which is a 650 CFM on the exact same power plant. I have a mild flat tappet cam with a .280 lift at 050. I struggled for a while with whether to go from the mechanical advance to a vacuum advance. There are endless opinions so it comes down to a matter of what you feel best with. Let me list the things I found wrong with my setup and you can do a mental checklist.

1. I found several gaskets in the carburator had been compromised, it had set up for a period and they were dried out rupturring when I put the gas to them.
2. The floats had been in the car for some time and were compromised, I eventually replaced them
3. The float bowl setting was up halfway in the glass window. For my mild setup I needed the fuel set to the bottom of the bowl
4. Because of the above issues fuel was blowing out the air horn, flooding the engine and washing the cylinder walls free of oil
5. The jetting was too large
6. The idle circuit slots were not adjusted correctly and the car was idling off the transition slots resulting in a stumble when accelerating
7. The accelerator pump was not properly adjusted, too much slack between the arm and the pump rod
8. A good test was wether the idle adjust ment screws actually adjusted the AFR or Vaccum
9. I went a while thinking the carburator was the problem, it wasn't completely the problem
10. My MSD ignition curve came in with the initial timing set to 16 degrees and the advance stop and spring setting I had brought me to 36 degrees by 3000 rpm
11. The car was basically starving for timing at lower rpm. you dont have that problem with the vaccum advance if it is setup right. The issue is how much the distributor will advance mechanically
12. With the vacuum advance, it doesn't alter the timenig under WOT (check me out on that)
13. The advance springsets were too light and the weights were bouncing around inconsistently
14. There is a lot more but these are starts. I got a lot of help from Tuning MSD Distributors Call em, they advocate vacuum advance