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Dorch Engineering S58 flex fuel ECA kit for BMW S58 — G80 M3 / G82 M4 / G87 M2

Dorch Engineering S58 Flex Fuel ECA Kit

$1,045.00

Dorch Engineering plug-and-play Flex Fuel ECA (Ethanol Content Adapter) kit for the S58. Reads ethanol content from a CAN-based Continental flex-fuel sensor and broadcasts the value directly to the DME — full flex fuel operation with no piggyback ECU, no datalog-and-flash dance, no fueling assumptions baked into the calibration.

What this enables

The S58 supports E85, E70, E30, and any pump-blend in between at the calibration level — but only if the DME knows the actual ethanol content of what's in the tank. Without a flex-fuel sensor, the calibration has to assume a fuel grade (typically 93 octane) and trim conservatively at sustained boost. With the Dorch ECA Kit installed and a Continental flex-fuel sensor in the fuel line, the DME reads ethanol percentage in real time and the Esse Werks Stage 2 / Stage 3 calibrations target full power on whatever blend you're running.

Real-world output difference

Owners running higher-ethanol blends report meaningfully more power than the same Stage 3 calibration on 93 octane — the flex-fuel infrastructure is what opens the upper end of the S58's tune-able envelope, because the DME is targeting real ethanol content instead of trimming around an assumed fuel grade.

What's in the box

  • Dorch ECA controller (CAN-based, plug-and-play to the OEM DME wiring)
  • Mounting hardware
  • Installation documentation

What you ALSO need (sold separately)

  • Continental flex-fuel sensor — plumbed into the fuel feed line
  • Stainless fuel line fittings to match your existing fuel system
  • A calibration that supports flex fuel (Esse Werks Stage 2 or 3 S58 with flex fuel option selected at intake)

Install

A workshop job at a competent shop — see the spec row for the estimated install time. The ECA controller mounts in the engine bay or under-trim area. Flex-fuel sensor installation requires a fuel line tap (best done at the fuel filter or rail inlet). Calibration re-flash after install to enable flex fuel maps.

Fitment

2021-2026 BMW G80 M3, G82 M4, G83 M4 Convertible. 2023+ G87 M2. 2020+ F97 X3 M, F98 X4 M. Confirm chassis at intake.

If you're sourcing fueling alongside the calibration, the Fueling Kit — S58 bundles the matched parts + tune for 8% under à la carte.

Fits engine S58
Fits chassis G80 · G82 · G83 · G87 · F97 · F98
Category Fuel
Manufacturer Dorch Engineering
Install effort ~2.5 hours

Ships from Boca Raton, FL.

WHY WE SHIP DORCH ENGINEERING
Dorch Engineering fills the gap where a single fuel system runs out of injector or pump to feed the power a build is asking for. Their high-pressure fueling work is built for the direct-injection BMW engines that hit a fuel-delivery wall before they hit a mechanical one. We choose Dorch when a customer commits to ethanol content or big-power targets that the factory HPFP and DI injectors can no longer support cleanly. This is fueling for the upper end of a build, where getting the supply right is the difference between a calibration that holds and one that runs lean where it matters.