Spool Performance BMW N55/S55 Wireless Bluetooth Ethanol Content Sensor/Gauge & Flex Fuel Kit – E85 Fuel Composition Analyser with App, 6AN PTFE Lines – F20 F21 F22 F23 F30 F31 F32 F36 M135i M235i M2 335i 435i F80 M3 F82/F83 M4

Spool Performance Ethanol Content Monitor for BMW N55 and S55 - app connected fuel alcohol sensor kit

Run higher octane blends with confidence. This Spool Performance phone-connected ethanol content monitor gives live fuel alcohol percentage and fuel temperature straight to your smartphone, so you can blend accurately, keep your maps safe and extract consistent power on everything from E0 to E85. Perfect for enthusiasts building flex-fuel BMWs who want a tidy, gauge-free solution with robust, ethanol-safe lines.

We use this kit on our own builds and it has been one of the most reliable upgrades we recommend. Customers love the accuracy, the simplicity of wireless monitoring and the quality of the 6AN PTFE braided lines and fittings. If you are searching for a BMW fuel composition reader, N55 ethanol gauge alternative, S55 flex-fuel setup, E content meter, Bluetooth fuel alcohol analyser or an app-based ethanol percentage monitor for BMW - this is the proven choice.

Why an ethanol analyser matters for E blends

Pump E85 can legally vary from about 51 percent to 85 percent ethanol. If your mix is lower than expected, performance suffers and engine safety margins shrink. A live fuel composition reader shows exactly what is in the tank, letting you hit target blends like E30, E50, E60 or E85 with precision and tune your BMW N55 or S55 safely.

Main benefits

• Real-time ethanol percentage and fuel temperature shown in the companion smartphone app
• Low-energy Bluetooth connectivity - minimal phone battery draw and no interference with other devices
• Reads in-tank ethanol percentage via the supplied flex-fuel sensor
• Fuel temperature display in Fahrenheit for repeatable data logging
• Free Spool app includes an easy blend calculator to hit your target mix every time
• Upgraded 6AN PTFE core stainless braided hose - fully ethanol compatible and built for high pressure
• Two hose routing options for a clean install:
  • HPFP to fuel tank - long line
  • HPFP to OEM line - short line
• Premium anodised aluminium PTFE hose ends for a leak-free seal

Ideal use cases

• N55 and S55 BMWs running E blends or full flex-fuel strategies
• Street, track and fast-road cars needing accurate fuel alcohol data
• Owners who want an in-app ethanol gauge without adding hardware in the cabin

Vehicle fitment - BMW applications

Designed for BMW models with N55 or S55 engines, including:

• 1 Series - F20 F21 M135i and M135ix
• 2 Series - F22 F23 M235i and M235ix, plus F87 M2 with N55
• 3 Series - F30 F31 335i
• 4 Series - F32 F33 F36 435i
• M cars - F80 M3 S55, F82 M4 S55, F83 M4 S55

Companion app

The free Spool app makes blending simple. Use the built-in calculator to create E30, E50 or any target mix. When the analyser is connected, the app auto-fills your current ethanol percentage for quick, accurate calculations.

Real results

We have installed and run this Spool Performance ethanol content kit on multiple cars. Feedback is consistently positive for accuracy, stability and the durability of the PTFE braided lines. It is a go-to choice for enthusiasts who want safe, repeatable E blend performance on N55 and S55 platforms.

Fitting and support

Professional installation available at MJ Modifications in Warwickshire - request a quote via info@mjmodifications.co.uk. For mail orders, we can complete a compatibility check before dispatch. Please include your UK registration or the last 7 characters of your VIN at checkout.

Part number

SP-EANS55

Manufacturer

Spool Performance

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