engine bogs down

it idles and runs great once warm, starts great its a fresh engine with about 500 miles on it, but when i want to get on it from dead stop sometimes it just bogs out and i let of gas and its goes on its way fine, seems like it started when i was messing with four barrel and got it working, and like i say only does it from dead stop, wonder if i need to adjust choke . or if the 4 barrel starves it for gas some times, i hope i make sense its just odd when it started because it never did it until i got 4 barrel working. thanks