Is my Carb too big?

[chargedstang89]

I have a stock crate 350 from GM that I put in my truck. It's an '85 gmc 1/2 ton 4x4. It has 33" tires, a 4" lift, 700R4 Tranny, and 3.08 gears, which were stock. The stock carb on it was trash. I got an Edelbrock model 1904, which is 795cfm. I thought that was way too big, but a couple of peple have told me that it isn't. My truck has little umpfh behind it when I'm driving down the highway or going up hills. I have to keep my foot in the throttle so much that it's ridiculous. Also, towing is horrible, as the truck seems to have no muscle. I know that with tall tires like that and 3.08 gears that I'm really down in the 2.xx range, but could my carb have something to do with that too. How about my horrible gas mileage, like only 100 or 110 miles per tank
(16 gallon) on the highway. Would I be better suited with a 650cfm carb? I also thought about putting a cam in the truck to try and help out, but I don't want to void the 3 year/36,000 mile warranty I have on the crate motor. Any advice? I'm a carb newbie...so, all is welcome.

J