If you want a good Y shape, you have to have the TB pushed out, i'm working on a new one with a Y !I can't have a Y as large a the one you're showing in the bottom because the space is not wide enough on the 986.
The wedge stabilises the air, maybe the cfd testings of the T alone don't show a big improvement with the wedge, but once on the car with the whole system, it should make a bigger difference.
You want the flow as clean as possible all the way to the valves (the you want turbulences in the combustion chambers).
In a naturally aspirated car, every bit counts
I have my midterms next week so I have to study and will not have too much time to do it this week, but after I will have all the time I need !