Anytime you do a TB on a TDI, the tensioner needs to be replaced... Waterpump is also a good idea, along with all the rollers...
Raf, these cars aren't geared for the 1/4.. To give you an idea of before and after..
Before (stock) : 90hp/155ftlbs.
After (nozzle + chip) : 130hp/240ftlbs.
These cars will NEVER be fast, but it does wake them up quite a bit. I have a few other goodies that I need to install in my car, after it's all said and done, I should be in the neighbourhood of 180-190whp and 350ftlbs.. Enough for all the rice rockets out there