For the racetrack, not the road. Thats why i said it is not recommended. For the road there is barely anything you can take out to reduce weight. You could put a spacesaver, maybe take some carpet out or clean off the dirt and crap from under the car but this would save you at most about 20kg. For the track though you can take out the rear seats, carpet, jack, spare tyre, roof lining, sound deadening and fit lightwieght seats or panels (if you have the money). Engine rebuilds This is another thing that is not recommended for a non mechanically minded being. If you know what you are doing, go for it but there are many mistakes that can be made when taking an engine apart or putting it back together. Everything has to be torqued to spec and installed correctly as well as actually having all the equipment to do so. --- Post updated --- Just looked up 2003 jetta kerb weight and apparently it wieghs roughly 3000 pounds or around 1350kg. Thats quite a bit for a car that has 115hp. As always i will bring my car into it, a 99 hyundai excel x3. It wieghs about 925kg (1000kg with me in it) and the engine in mine makes 99hp. That is about 9.3kg per hp. The jetta on the other hand is 11.7kg per hp. I took my excel for a quick squirt the other day to celebrate getting my P's and i have to admit, it is quite zippy at under 70-80kmh but as it starts to go over that, it really starts to become sluggish. If you want a fast car, a 1.35 ton (unloaded) behemoth is not the right way to go.