Cometic MLX Head Gasket - BMW B58 Gen1 (B58B30M0/M1), 83mm, .036in
Ships from the brand or distributor, usually in 3–7 business days
Make sure this fits your car
Fits: Gen 1 B58 (2016-2019 F-series: M140i, M240i, 340i, 440i, 540i, 740i, X3/X4 M40i)
- Shipping at real carrier rates
- 30-day returns on unused parts
- Fitment help before you buy
Cometic's MLX head gasket is a multi-layer steel replacement for the Gen 1 B58 (B58B30M0). Paired with head studs, it is the kind of gasket used when a build will run more boost than the factory gasket was designed to seal.
What you get
- Four-layer MLX construction in place of the factory gasket.
- 83 mm round bore.
- .036 in compressed thickness.
Good to know
- Cometic builds this gasket to order, so allow extra lead time.
- Professional installation is required.
Brand: Cometic · Part #: C14121-036
Gen 1 B58 (2016-2019 F-series: M140i, M240i, 340i, 440i, 540i, 740i, X3/X4 M40i)
| Model | Chassis | Years | Engine | Fits |
|---|---|---|---|---|
| M140i | F20/F21 | 2016–2019 | Gen 1 B58 | |
| M240i | F22/F23 | 2016–2021 | Gen 1 B58 | |
| 340i | F30/F31/F34 | 2016–2019 | Gen 1 B58 | |
| 440i | F32/F33/F36 | 2017–2020 | Gen 1 B58 | |
| 540i | G30/G31 | 2017–2019 | Gen 1 B58 | |
| 740i | G11/G12 | 2016–2019 | Gen 1 B58 | |
| X3 M40i | G01 | 2018–2019 | Gen 1 B58 | |
| X4 M40i | G02 | 2019 | Gen 1 B58 | |
| 640i GT | G32 | 2018–2019 | Gen 1 B58 | |
| M340i | G20/G21 | 2019–2024 | Gen 2 B58 (TU) | |
| M440i | G22/G23/G26 | 2021–2024 | Gen 2 B58 (TU) | |
| M240i | G42 | 2022–2024 | Gen 2 B58 (TU) | |
| Z4 M40i | G29 | 2019+ | Gen 2 B58 (TU) | |
| GR Supra 3.0 | A90/A91 | 2020+ | Gen 2 B58 (TU) | |
| 540i | G30/G31 | 2020–2023 | Gen 2 B58 (TU) | |
| 740i | G11/G12 | 2020–2022 | Gen 2 B58 (TU) | |
| X3 M40i | G01 | 2020+ | Gen 2 B58 (TU) | |
| X4 M40i | G02 | 2020+ | Gen 2 B58 (TU) | |
| X5 xDrive40i | G05 | 2019–2023 | Gen 2 B58 (TU) | |
| X6 xDrive40i | G06 | 2020–2023 | Gen 2 B58 (TU) | |
| X7 xDrive40i | G07 | 2019–2022 | Gen 2 B58 (TU) | |
| 840i | G14/G15/G16 | 2019+ | Gen 2 B58 (TU) | |
| INEOS Grenadier | Station Wagon/Quartermaster | 2023+ | Gen 2 B58 (TU) | |
| M340i | G20/G21 | 2025+ | Gen 3 B58 (48V) | |
| M440i | G22/G23/G26 | 2025+ | Gen 3 B58 (48V) | |
| M240i | G42 | 2025+ | Gen 3 B58 (48V) |
Not sure? Email sales@b58racing.com with your VIN.
- Ships from the brand or distributor, usually in 3–7 business days.
- Shipping is charged at the carrier's rate, shown at checkout. Orders over 70 lb ship by freight for a flat $99.
- Unused parts can be returned within 30 days. Some items are marked no-refund in their description.
Full details are on our shipping and returns page.
Guides for this part
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