The JB4 tuner for Alfa Romeo Giulia and Stelvio 2.0L turbo engines delivers up to 40hp at the wheels - no ECU flash, no workshop visit, no trace left behind.
Preloaded with Alfa-specific maps: pump gas, E85, and bolt-on friendly options
Wireless control via JB4 PRO app - switch maps on the fly, log data, adjust boost-by-gear, read and clear fault codes
True plug-and-play: no coding, no VIN lock, full compatibility with all driving modes
Made in the USA with 5-year warranty; includes rugged billet aluminium enclosure
Runs smoother than stock, no impact on fuel economy in normal use. Fast road or track day - it’s ready when you are.
