Subcategories:
Modifications 
Articles and reviews of elaborated and tuned cars written by fans. In Italian.
http://www.autoelaborate.com/
Chiptuning community dedicated to everything related to chiptuning; including ecu, remapping, obd-ii, and soldering stations. Offers news, forum, directory, and related services.
http://www.checksumm.com/
3. Racing TDI
Dedicated to one person's personal tuning project with a VW Golf TDI 110hp Highline. Features engine tuning information, pictures, and resources.
http://www.racingtdi.com/
Technical specs, photo galleries, wallpapers, screensavers, RSS feeds by category, and more automotive related resources.
http://www.supercarnews.net/
Portuguese language tuning portal. Includes pictures, project cars, forum, news, and virtual tuning.
http://www.tuning.online.pt/