Open the hood of an M340i and the B58 is hiding under a big slab of grey plastic. It is one of the best inline sixes BMW has ever built, and the factory cover gives it all the personality of a storage bin lid.
The Dinan Matte Carbon Fiber Engine Cover replaces that plastic on B58D-powered BMWs: the G20 M340i, G22 M440i, G42 M240i, G29 Z4 M40i and 2020 and newer X3 and X4 M40i. The base is real 2x2 matte twill carbon fiber, set off by opposing gloss carbon panels and white painted cylinder count callouts, with power stripes that nod to classic engine and valve covers from Dinan's past.
Dinan Matte Carbon Fiber Engine Cover Design and Weight
This is 100% genuine carbon fiber, not a wrap, a hydro-dip or a plastic overlay. The matte base and gloss accents play off each other as the light moves across the bay, so the cover has depth instead of reading as one flat panel. It is lighter too: Dinan weighs it at 2.9 lbs against 4.1 lbs for the factory cover.
Fitment is direct. It drops onto the factory mounting points, grommets are included, and there is nothing to cut, drill, code or tune. Keep your stock cover on the shelf if you ever want to return to factory. Dinan part number D590-0004. Sold by AutoTecknic, an authorized Dinan dealer.
What's Included
- 1 x Dinan matte carbon fiber engine cover with gloss carbon accents
- Mounting grommets
Key Features
- 2x2 matte twill carbon fiber base with opposing gloss carbon fiber and white painted accents
- Power stripe design with white painted cylinder count callouts
- 2.9 lbs vs 4.1 lbs for the factory cover
- Direct replacement for the factory B58D engine cover
- Grommets included
- Dinan-rated 0.25 hour installation
- Also offered in gloss carbon with matte accents (sold separately)
Vehicle Fitment
Fits these B58D-powered BMW models:
- BMW M340i / G20 Sedan (2020-2026): M340i, M340i xDrive
- BMW M440i / G22 Coupe and G23 Convertible (2021-2026): M440i, M440i xDrive
- BMW M440i / G26 Gran Coupe (2022-2026): M440i, M440i xDrive
- BMW M240i / G42 Coupe (2022-2026): M240i, M240i xDrive
- BMW Z4 M40i / G29 (2020-2026)
- BMW X3 M40i / G01 (2020-2024)
- BMW X4 M40i / G02 (2020-2025)
Not compatible with 2018-2019 X3 M40i and X4 M40i, which use the earlier B58 engine. Does not fit four-cylinder 230i, 330i or 430i models, or the Toyota GR Supra.
Installation Notes
About 15 minutes, no tools needed for most cars. Set the new cover on a soft towel so the finish stays clean.
- With the engine cool, lift the factory engine cover straight up off its mounting studs.
- Check that the supplied grommets are seated in the Dinan cover.
- Align the Dinan cover over the mounting studs and press down evenly until it seats.
