so im changing my exhaust again right now ive got stock back to the cat then a 2.5-3 inch adapter to the muffler and a turndown to dump it before the axle. im wondering if i just get a 3-2.25in y-pipe and run rear duals(yes i know not really duals) would it flow fine.

 

You would be better getting a muffler with a single in dual out.

 

You should go with one inlet and dual outlet. From my cat, there's 1 intermittent 2.5 inch pipe. then the muffler has 2 2.25 outlets at the tail pipe.

 

i have 2 mufflers that are 2.25 in/out that are one in one out and i dont want to buy another so im trying to decide whether or not to take the one off and put one of the others on

 

Well then that's more off a preference thing then anything else. We can't answer that for you. It's all up to you.