i am on a tight budget and am wondering should i get a 6350 and a 7850 and a good psu or a 8320 and r9 270 and a bad psu?
Well first off I wouldn't get the 6350. Get the 6300. It isn't that much slower. The R9 270 is basically a 7870 and is faster than a 7850 so I have no idea why you'd get that latter. The 8320 will be faster but not that much and in game the GPU is more important.
Never skimp on the PSU unless you want to destory all of your other components.