carb question

buying a carb 750 double pump is there much difference in perf , with a carb that has top cut for better air than one thats not ? thanks my 750 looks great but will not run the motor ,hit the gas pedal squiters squit gas , but wont run, tries to run if you pump the **** out of it, put another carb on fires right up, been apart several times cleaned ,checked cant find trouble new needle and seats,set gas level,getting 6 to 7 lbs pressure , not flooding ??????????
Sounds like some one has the wrong gaskets or metering block on it not letting your boosters pull the fuel out of bowels.. Because your squitters are on a different circuit than your idle circuit ..I have a proform center for that carb for sale..

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