RENNtech ECU+ Upgrade | W222 | S 550 | 540HP / 705LB-FT | 4.7L V8 BiTurbo | M278 | MY2014-2017 jaguar-xj--351---2009-2019--esr9874497 Rated by RENNtech (peak @wheel):

Rated by RENNtech (peak @wheel):              735 whp @ 6

consistent sound

Our intermediate ECU tune increases performance from 556 HP and 550 lb/ft torque to 638 HP and 695 lb/ft at the crank

All this while still maintaining the same approach angle as the OE front fascia so the RENNtech splitter retains the same clearance for parking stops and steep driveways

RENNtech ECU+ Upgrade | W222 | S 550 | 540HP / 705LB-FT | 4.7L V8 BiTurbo | M278 | MY2014-2017 jaguar-xj--351---2009-2019--esr9874497 Rated by RENNtech (peak @wheel):ECU+ Upgrade 540HP 705LB FT Gains: +66HP +139LB FT RENNtech HHT (hand held tuner) allows you the unlimited ability to switch between tuned and stock ECU programming and requires no ECU removal! Our proprietary tuning module stores both the RENNtech tuned file and your vehicles stock file. The module plugs directly into the OBD2 port and delivers the file you choose directly to the ECU. Programming takes only a few minutes and the vehicle can be