the "2.8T" is a turbocharged VR6. They just swap the normally NA motor and turbo it.

They're extremely difficult swaps, but it has been done. HPA did it, a twin-turbo VR6 engine in a beetle, and routed through an audi TT's AWD system. Dont ask how, I just know it ran under 11.5.

The 1.8T powers the GTI a little better, but its still a respectable engine for a beetle.