Tech articles available on AudiWorld.com: Modifications to my A4 and S4 (some friends cars too).

• Forge-Milltek exhaust
• Torn bypass valves
• Bypass valve testing
• Throttle body boot replacement
• APR BiPipe (no more TBB troubles!!)
• Intake air charge temperature
• Installing an air filter
• K&N air filter testing
• Intercooler mister
• Seat modification - Making more headroom
• Bose stereo upgrade - an upgrade not worth performing
• Adding a subwoofer
• A4 Bose stereo system testing
• XM Radio Install
• Valentine 1 hardwire
• S4 performance testing
• Washer nozzle adjustment
• S4 plus zero tire upgrade
• Installing AP racing brakes
• Auto-dimming mirrors
• Digital boost gauge
• VDO boost gauge install
• OC.T S4 boost gauge
• K04 turbo upgrade
• Reminder: timing belt replacement
• Garmin StreetPilot install
• Lip spoiler install
• Driveline stabilizer
• Driveline mount testing
• Installing a Factory Armrest
• The excellent Passat Cupholder
• Lidatek LE-30 Install (B6 S4)