Hey guys,

I know this has been beat to death but i havn't been able to find an answer to a specific question. This is regarding my 63 chevy truck which is currently equipped with a stock 327 and edelbrock intake. the previous owner put a 750cfm edel carb on it, there is serious stumble when I floor it. My knowledge so far says that is because its too big and the math tells me a 500cfm or 600cfm would work. I'm leaning towards the 500cfm as this truck sees no racing and only the occasional burnout. I'm thinking better gas mileage and really good throttle response. However, the quadra-jet is supposed to get better gas mileage because it has smaller primaries. The only problem though is that they are all 750cfm. So will I get the same stumble I get now when i floor it with a 750cfm quadrajet? Also, will the gas mileage be similar (if i can keep my out of it ) between a 500cfm and a 750cfm quadrajet? Thanks guys! (feel free to throw in anything i havn't thought of.....can't go 2 barrel though...I don't want to neuter my truck )