There are so many possibility's for TT engine's.
Say the TTS get the S3 2.0TFSI engine with 265-280 hp.
The TT 3.2 VR6 can be dumped or get a upgrade to either a 3.2 FSI with 250-265 hp or a 3.6 FSI with 280-300 hp.
The supposed TT-RS can get a 3.6 VR6 FSI with 280-300 hp, a 2.5 R5 TFSI with 330-375 hp, a 3.2 VR6 TFSI with 420-480 hp, or even a 3.6 VR6 TFSI with 475-540 hp.
But i doubt it will ever getting any more then 365-400 hp.
And when you look at all the possibility's a 3.2 VR6 TFSI is the most logical choise.
You can get by putting on a simple K03 turbo at leasted 320 hp and up to 425 hp with a K04 turbo out of it.
Beside this Audi have Nordschleife test data of turbo and bi-turbo charged VR6 engine's from the TT Mk1.
The only problem was that the TT Mk1 body could not handle the power.
Hans.