|Our latest kit for the s63tu M5/M6, the new JB4 BETA includes functions never before available to the platform including on the fly map switching, boost limiting in lower gears for improved traction, an in dash boost gauge, full CANbus data logging, code read/delete, and the ability to tune for as much boost as your octane and/or fuel system will allow. For most running pump fuels expect power gains of around 100whp over stock. For those who really want to push the factory turbos with a methanol injection kit and higher octane fuel power gains of up to 240whp over stock are possible. The JB4 also supports larger s63tu turbos. We’ve had customers report as much as 820hp to the wheels using simple Stage1 turbos!
Installation is more involved than our Stage1 tuner in that you must run a wire to the cabin for the OBDII CANbus connection and the BCM connects to the wastegate solenoids behind your passenger side intercooler. Connecting the BCM requires draining some of the intercooler coolant and refilling the system after you’re complete. For those who simply want a Stage1 with better logging, in dash gauges, boost by gear, code delete, and will be happy with 20psi or less, the BCM is optional. For those wanting to push more than 20psi (maps 2+) the BCM is required.
For those running a DCT transmission we’ve found the factory clutch packs are only good for around 640whp before they start slipping. If you are planning for more power than this plan to upgrade to Dodson clutch packs sooner or later. Checkout our s63tu tuning forum on n54tech.com for the latest map guide, dyno charts, and tuning suggestions.
For the current map guide, firmware, and notes refer to this thread: