Snow Performance BMW Water Methanol Injection Anti-Siphon Solenoid Valve Upgrade SP30105 - High-Flow Stainless, Methanol-Safe, 1/8" NPT - Fits N54 N55 S55 B58 S63

SP30105 Anti‑Siphon Valve for BMW WMI Systems

Lock in reliable, clean water injection with the SP30105 stainless anti‑siphon valve. Built for demanding BMW forced‑induction setups, this methanol‑safe shut‑off valve stops unwanted drainback, gravity feed and run‑on when your pump is not energised. It keeps lines sealed until the controller calls for flow, giving consistent atomisation, safer tuning headroom and repeatable performance on road, track and fast‑road builds.

We use this part on our own projects and customer cars. The result is simple. Rock‑solid control, no spurious dribble into the manifold, and confidence when running rear tanks or low‑mounted nozzles.

Standout benefits

• Positive shut‑off for your WMI line to prevent back‑flow and siphoning
• Ideal when the nozzle sits below the reservoir, under vacuum, or with a boot‑mounted tank
• Stable fuelling under boost for tuned turbo BMW engines
• Quick to install with included push‑fit adapters and bracket
• Proven on high‑power street cars and track toys looking for dependable injection control

Technical details

• Part number: SP30105
• Stainless‑steel body and internals for excellent corrosion resistance
• Methanol compatible throughout
• High‑flow design to support demanding WMI setups
• Ports: 1/8 inch NPT female both sides
• Includes two 1/8 inch NPT to 1/4 inch rapid‑connect fittings
• Includes mounting bracket and screws

Compatibility and applications

Works with Snow Performance Boost Cooler systems and upgrades, and with most water‑injection kits using 1/8 inch NPT connections. Suitable for turbocharged and supercharged builds up to 2.1 bar or 30 psi.

Popular BMW engine coverage includes N20, N54, N55, S55, N63, N63TU, B38, B48, B58, S63 and S63TU. Perfect for WMI line shut‑off on direct‑injection and port‑injection applications alike.

What you get

• 1 x SP30105 stainless shut‑off valve with 1/8 inch NPT ports
• 1 x bracket with fixings
• 2 x push‑fit adapters 1/8 inch NPT to 1/4 inch

Fitting service

Want it installed by specialists who build and tune these cars every day? Book professional fitment with MJ Modifications in Warwickshire. Request a quote: info@mjmodifications.co.uk.

Pro tip

Using ProLine steel braided hose sets for even greater methanol resistance and abrasion durability? Choose the Snow Performance ProLine solenoid option matched to those lines.

Pre‑dispatch check

Add your UK registration or last 7 digits of your VIN at checkout and we will confirm suitability for your setup before shipping.

Why enthusiasts choose this valve

Trusted by tuners for consistent shut‑off and leak‑free operation. Customers report smoother delivery, better peace of mind with rear reservoirs and cleaner plugs thanks to precise on‑off control.

Search phrases and related terms

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