A small engine can run on large twin 4 barrel carbs since they're not flowing at full CFM at idle. Where things go South is when they open and begin to flow, the port velocity drops off and so does low end torque.
Right about the same time, the velocity drops off, the fuel and air begin to separate and you end up with a poor burn rate during the combustion cycle. In extreme examples it will foul the plugs to the point the everything stops.
I learned this very important lesson when I was about 16 and tried to run a set of Isky Caliopie Stacked Injectors on the street that I bought at a local speed shop (Dale Welch Auto Sales in KCK). The look I got from my girlfriend's Dad when I jumped out with a bottle to prime them as we were leaving her house was worth it (almost).
For all you would be tuners out there; you're not running a *real* cam profile unless you need a vacuum reservoir to keep the brakes going
