Home » CarBahn BMW Flex Fuel Tunes for S58 & Gen 2 B58

CarBahn BMW Flex Fuel Tuning

CARBAHN ETHANOL FLEX FUEL TUNING

Unlock another level of BMW performance with ethanol-adaptive tuning. Choose your engine, then build your flex fuel setup.

Two engines. Serious potential.

Choose Your Platform

BMW M Performance

S58 Flex Fuel

Turn up your M car with adaptive ethanol tuning and maps built around the way you drive.

828 HP +275 HP OVER STOCK
744 LB-FT +243 LB-FT OVER STOCK

G87 M2 automatic • E40
Calculated flywheel figures. Stock: 553 HP / 501 lb-ft. Output varies by model and configuration.

Platform Fitment

  • G87 M2 / M2 CS — Automatic
  • G80 / G82 / G83 M3 & M4 — Competition, Competition xDrive, CS and CSL, as applicable
Build My S58 Tune

Generation 2 Only

B58 Flex Fuel

Bring ethanol-adaptive performance to your Gen 2 B58, with a tune tailored to your setup.

611 HP +196 HP OVER STOCK
640 LB-FT +167 LB-FT OVER STOCK

Gen 2 B58 • 93 octane + E40
Calculated flywheel figures. Stock: 415 HP / 473 lb-ft. Output varies by model and configuration.

Platform Fitment

  • M240i / Z4 M40i — 2021–2025
  • M340i / M440i — 2021–2024
  • X3 M40i — 2021–2022
  • X4 M40i — 2021–2023
Build My B58 Tune

The Setup Behind The Power

Your Fuel. Your Platform. Your Maps.

01 / ETHANOL

Adaptive By Design

Ethanol offers greater knock resistance and charge cooling. With the required sensor, the tune adjusts fueling, ignition and boost as ethanol content changes within the supported E0–E40 range.

02 / PLATFORM

Choose Your Flash Platform

Build your setup with bootmod3 or MHD. Select the compatible license, connection hardware and flex fuel sensor you need, or use equipment you already own.

03 / MAPS

Make The Tune Yours

Start with your base octane map, then select up to three additional maps for street, track or utility use. Optional custom maps tailor eligible selections to your hardware and goals.

Figures shown are calculated flywheel results, not wheel horsepower. Flex fuel tuning is not covered by CarBahn’s Factory Matching Warranty or Protection Plan. Not legal for use in California on pollution-controlled vehicles.