Add Wish List Quick view Choose Options RaceChip XLR5 - Mercedes-Benz S-Class (W221) (from 2005) S 63 AMG (525 HP/ 386 kW) Next-gen throttle response for your MB S-Class (W221) S 63 AMG The RaceChip XLR5 is our latest throttle response controller with advanced calibration and ultra-precise response curves. The most... RRP: Was: Now: £199.00 - £249.00 Choose Options Compare