At a "Stage 2" level (requiring exhaust and cooling upgrades), these tunes can push the B5 S4 to 18–22 PSI of boost , resulting in gains of 90–125+ hp over stock. 4. Supporting Modifications & Maintenance To safely run this setup, enthusiasts often include:

These software revisions optimize fuel delivery, ignition timing, and boost pressure.

Features a 6-speed manual or 5-speed Tiptronic automatic, with Audi's signature Quattro all-wheel-drive system. 2. The "V2.4" Modification

This mod is typically paired with larger aftermarket turbos (like RS4 K04s or bigger) to maximize top-end performance. 3. Performance Software (V1.46)