if you just want your exhaust louder while keeping the same tone. just take off the exhaust seal between the mid pipe and muffler. My car use to idle really loud and it was loud when i took off before i replaced mine.

Plus if you don't like the sound, just put the exhaust gasket back on and your back to stock noise level.

Total cost = $0 plus 30min of labor.

 

I believe most of us call that an "Exhaust Leak" not really an upgrade...

 

its a leak on the muffler side rather then the engine side so your not really losing performance since the muffler is simply used to muffle sound. Basically the same as running open muffler but not as obnoxiously loud

The OP wanted the Y pipe for increased sound and tone while keeping the stock tone rather then hp gains. My solution gives him that with no cost.

 

If you want to do that just run an electronic exhaust cut out and run open muffler when you track and closed as a daily driver don't be cheap and remove a gasket

 

the point is it won't hurt performance like you implied on your previous post, since its on the muffler side not the engine side and it'll add to the engines noise level like the OP wanted.