Originally Posted by xxllmm4
Hey everyone, I was just thinking. Why don't you see any three hole carb spacers? Seems like it would be the best of both worlds. I have herd a few people have done it themselves but I have never seen any dyno charts or comparisons.
I'm at a loss to see any advantage. On a spread bore like you are showing, the motor runs all the time on the two primaries, which are the little bores at the front. When you mat the loud pedal, the larger secondaries kick in, both at the same time. I see no advantage in cutting out the wall between the secondaries. They're gonna flow the same, no matter whether there is a wall between the bores or whether there isn't. The only way you could make a difference is like timothale said, with a Holley 3-barrel because one long oval throttle plate has more area than two round ones like a Quadrajet.
Speaking of spacers, there is no arithmetical formula for making them work. Each motor is a combination unto itself and what works on one motor will not necessarily work on another motor.