The S63 build path
The S63 is a 4.4-litre twin-turbo V8 running across two banks. From the factory it is held back on boost, timing and fuelling to clear emissions regulations in every market it sells in. A custom Stage 1 remap moves all three. No parts to source, no rolling road needed. Stage 2 adds downpipes, which lets both turbos breathe properly and unlocks the bigger top-end numbers. E85 and harder builds are quoted per build, calibrated individually around your fuel and hardware. One thing specific to the S63: it is a twin-ECU engine. Where an unlock is required, it applies per ECU. Samuel confirms from your VIN before the build starts and includes it in the quote if needed. Every tune is calibrated from your datalogs, not a generic off-the-shelf file.