When selecting a carburetor, is it better to consider the cfm or the Venturi and throttle bore diameters? It appears that between manufacturers some of these diameters are different with the same advertised sized carb. I'm guessing that the difference is between the street/strip type carbs compared to the more race oriented ones. I have no real baseline to start with since my current Q850 carb has proven very difficult to tune to have a true baseline to reference. But I can say that I'm currently jetted the same as a stock Q750. I am not sending this back for the money that they want, so I'm gonna just buy another one. So in essence I'm starting over and could use some help / recommendations. If it is general consensus that a 4150 style 850 cfm is not to big of a carburetor for my set up, I was looking at the Holley 850 XP series purchased direct from them. Mainly because of the idle bypass feature and it has all of the same features as my quickfuel. or would I be better off trying one of the street/strip type carbs?