I am going to twins, but I've been saying that for years. I'm going to go ahead and pull the trigger on a T4 manifold from ATS (I have a contact there) and get a manifold blanket and a turbo blanket for the exhaust side.

 

Gonna need to be a T3 unless you are going to send your turbo off for an exhaust housing change.

 

Is the stocker a T3? Because it's a lot smaller than my turbo housing.

 

Yes, the stocker and your HTT turbo are T3. T3, T4 are the size of the exhaust flange.