Not sure on the tech info on the car... I am putting a 89 RX7 13B turbo w/intercooler on mine that will be about 300hp when done... adapted to a Porsche 5 speed running radiator up front in the spare tire well....
You can find out more info on conversions at
vw engine conversion message board
I decided to go with the 13BT after seeing one in a Sand rail... It is a much cheaper way to get 300 hp in a bug and it is water cooled so good for long trips in the summer...