I need to choose a carb and dont know what to get. Any thoughts?

I have a 67' Land Cruiser. It's all Chevy though. I have a 350 from a 69 Camaro with a Quadrajet that someone else put on. I rebuilt the thing and it still sucks. Im currently building everything else from the ground up but when it did run, if I hit a bump hard enough it was almost as if the carb would load up and then it would stall out. I would be able to start it again but only after I let it sit for about 15 or 20 minutes. Im not happy with this carb. I am seeking an alternative. I dont care about the emissions so the skies the limit. The thing is though that I really dont know beans about carbs. Can anyone point me in the right direction?