I had not considered vacuum signal when running my 3 Holleys. First they are 280 CFM each. (actually off AMC V-8's). I have watch guys use the same Clifford tubing manifold using 500's and it did not perform as well. I have 12-1 compression with a 310 adv deg cam and .615" lift. All of this works as used. The power valves are removed from the carbs. When I did drag race it the car always stumbled off the line. I learned to drive through that.
I have also used a single 2 barrel from Braswell which flow over 700 CFM. A very trick carb. With many annular discharge holes in the venturi this carb responds very well to the 50+ cubes of each cylinder. The vacuum signal is perfect but a slightly bigger 4 barrel with the 4 venturis gave me a slightly higher mph. The 2 barrel gave better ET's
If were to use a 3 carb setup on the street the center one for sure would be smaller if using a progressive linkage. All 3 would be small for straight linkage. I like a street engine with as much compression as possible to run without detonation and a cam which doesn't kill the low end. To me that's where a few degrees advancing come in.......
This a great discussion. There are many theories but hearing from practical use on what works and doesn't work gives a guy a chance not to make as many mistakes as many of us did in the past....J.D.
