i've have my 434 about done, i am coming to point also wut exhaust i should do, i want to try an x-pipe but would it be worth it for all that work, because a Y-Pipe doesn't seem to me like it would flow, i would be resrticted too much, and this is a street car

I dont know the specs about your engine or car but if its a street car I'd go with a Mufflex system "$$$$" permitting. Hooker long tubes into a dual 3 inch Y-pipe into a single 4inch cat back system.