The 2002-2005 Audi A4 quattro combines timeless Audi design, turbocharged performance, and legendary all-wheel-drive capability. Enhance your A4 quattro with APR performance upgrades, including ECU tuning, intake systems, exhaust upgrades, turbocharger enhancements, and supporting hardware engineered to increase power, improve responsiveness, and maximize driving enjoyment.

APR’s Engine Hardware delivers true performance engineering—meticulously crafted intake systems, turbocharger upgrades and support components built to integrate with calibration upgrades and boost your vehicle’s breathing, response and power delivery on VW, Audi, Porsche and other European platforms.