Make tremendous amounts of power on pump gas!

Water/Methanol/Alcohol injection commonly referred to as WMI allows you to make tremendous amounts of power on pump gas. The effect is similar to running 100 octane race gas or E85 fuel all the time with the additional cooling benefits allowing for more power than you can make on race gas or E85 alone. For those that don't have easy E85 access WMI adds a ton of power over pump gas, and for those running E85 WMI can still be very useful for its charge air cooling and fuel volume benefits.

The key to a safe and effective WMI setup is tuning integration. The B58 BMS WMI kit integrates to the JB4 tuning system allowing for precise mapping based on boost, throttle position, engine speed, intake temperature, advance, gear, and other data elements available to the JB4 through its CANbus system. In addition, a pump flow signal is fed back to the JB4 allowing for a safe and smooth progressive boost mapping. If the tank runs empty or flow drops for any reason the JB4 will safely back down performance to avoid detonation. Boost is held low until WMI is properly flowing to avoid tip in knock common with non-integrated WMI setups. In addition WMI can be activated or disabled right from the JB4 Mobile app , will automatically disengage during traction control or safety map situations, and WMI flow data can be displayed via your JB4 Mobile logging device.

The BMS WMI kit includes our new 3.5 gallon integrated stealth tank, FSB JB4 Water/Methanol Injection (WMI) Controller, a high quality Aquatec water/methanol Injection (WMI) pump made to our specifications, BMS BM10 super atomizing water/methanol injection nozzle, high speed solenoid with leak-free compression fittings, 18' of steel braided line, 24" steel braided lines with AN fittings, an AN 90º pump fitting, inline filter, and all required wiring, brackets, and mounting hardware.

This water/methanol injection (WMI) tank is a completely custom design that neatly hides away in the left side trunk cavity found in most G20 G22 & G80 M3 & G82 M4 BMW vehicles. The pump mounts directly to the back of the tank allowing for a quick, clean, and completely stealth installation. The bottom of the tank includes a rear sump allowing for consistent performance even as the tank drains. Includes 2-way vented black plastic cap, a compression pump feed fitting, and 12" of vinyl WMI line for the non-pressure side of the WMI pump. Our unique tank can also be purchased separately here.

We also offer an optional upgraded blue billet tank cap with 1-way check valve available here.

This kit includes a BM10 (10 GPH or approx 750 ml/min) injection nozzle suitable for most B58 applications. Mounting requires an 1/8" NPT port or our throttle plate adapter.

Optional plug and play Water/Methanol Injection (WMI) adapter for Gen 2 B58 BMW motors

We've designed this plug and play adapter for quick installation and removal of BMS dual nozzle water/meth kits without having to replace the factory charge pipe. Simply unscrew three bolts, insert the CNC machined adapter with integrated o-ring in place between the throttle body and intake manifold, and tighten the included longer length bolts, to allow mounting of two meth nozzles with a perfect seal.

Vehicle Fitment

BMW 3 Series
• 2020-2023 G20 B58 BMW M340i including xDrive

BMW 4 Series
• 2021+ G22 BMW M440i including xDrive (requires modification for tank fitment)

What's included
• (1) G20 Stealth Tank and Mounting Hardware
• (1) FSB JB4 Water/Methanol Injection Controller
• (1) BMS water/methanol Injection pump
• (1) BM10 Water/Methanol Nozzle
• (1) 12.5' of steel braided hose (straight and 90º fitting)
• (1) 2' of steel braided hose (straight and 90º fitting)
• (1) 18" of PTFE line (tank to pump)
• (1) Billet 1/4 push male to -4AN male 90º (pump out)
• (1) 1/4 push male to female 90º (pump in)
• (1) Solenoid
• (1) Gen 2 B58 billet throttle body adapter (optional)
• (1) 15' (-) Negative black wire
• (1) 15' (+) Positive red wire
• (7) wire wire nuts
• (1) inline fuse holder

Optional: Gen 2 B58 Throttle body adapter

JB4, BMS intake, BMS charge pipe, BMS WMI, ~93 octane, factory flash

Optional upgraded blue billet water/methanol injection (WMI) with 1-way check valve available here.