ok another update...
it'll rev up clean all the way, without the air box on.
it will only start with the choke on, even when its hot. and it sounds like it runs out of gas and dies randomly.
i can take it all the way up in 2nd and it'll run up there with no pops or hesitation, but it feels like it loses power at the top.
it runs the same with the 290 and 310 jet, but it seems to start easier with the 290.
and it'll only run/start with the mixture screw all the way in.
any suggestions?