Cam really doesnt sound like the problem. A change in camshaft will not force the engine to starve at low rpm. Sure if its a massive cam and you go to rev it to like 7500rpm the weber might not be enough but everything else should be fine. The bigger the cam the more sluggish down low it will be but it will still be quite drivable. Before going through the hassle of taking out the engine to change what doesnt even sound like the problem to me check everything else.