Semantics. What sort of "dual quads"? Vacuum secondaries? Quite plausible, especially if they are flowing 500 cfm, give or take. Even the smallie 'Vettes had dual quads. A VS 2X4 setup that never opens the secondaries is probably not flowing much more than 600 cfm...ever. Even the Six Pack running about town on the center carb is only using 350cfm. A 2X4 manual secondary setup will probably lose you a lot of races unless you do a lot of dyno tuning and jetting work. Same goes for a MS triple deuce setup.
