MST BMW G42 M240i & G20/G21 M340i B58 Performance Intake Kit

Unlock the full potential of your BMW G42 M240i or G20/G21 M340i with the MST B58 Performance Intake Kit, designed to deliver increased power, sharper throttle response, and an enhanced turbo sound. This premium intake system replaces the restrictive factory airbox with a high-flow design that ensures your turbocharger breathes cooler, denser air for improved performance.

Constructed from black powder-coated aluminium, the 4-inch intake pipe and heat shield work together to isolate the air filter from engine heat, maintaining consistently low intake temperatures even during spirited driving. The dry cone air filter is easy to access and maintain while providing outstanding filtration and flow compared to the OEM setup.

Dyno-tested results show gains of 15–20 horsepower, alongside improved throttle response and a deeper, sportier induction tone that perfectly complements the B58 engine’s character. For those who want to showcase their setup, MST also offers optional clear filter covers to make the dual-cone filters visible under the bonnet.

Key Features

• Designed for BMW G42 M240i & G20/G21 M340i B58 engines

• Increases power by 15–20hp (dyno-tested results)

• Improved throttle response and enhanced turbo spool sound

• 4” black powder-coated aluminium intake pipe with dry cone air filter

• Heat shield divider reduces intake air temperatures

• Optional clear covers available for a custom visual touch

• Direct fitment using the supplied fitting kit

• Easy maintenance and long-lasting filtration performance

What’s Included?

• MST B58 Performance Intake System

• Black heat shield divider

• 4” high-flow dry cone air filter

• Full fitting kit and installation hardware

Compatibility

• BMW G42 M240i (B58)

• BMW G20 M340i (B58)

• BMW G21 M340i Touring (B58)

Unless explicitly stated otherwise, all products sold by R44 Performance Limited are designated RACE ONLY and are solely for competition or off-road use limited to racing formally sanctioned by a recognized racing organization. Any other use, including recreational off-road use, may violate local, state, and Federal laws. R44 Performance Limited does not implicitly or explicitly confirm the legality of using any products it sells on public roads; that is entirely the responsibility of the consumer.

It is the responsibility of the customer to check with all federal, state local and environmental laws before ordering and installing a product. R44 Performance Limited is not responsible for any fees, fines or costs that a customer may incur as a result of failing to check with federal, state, local or environmental laws before ordering and installing a product.

We get a large number of custom orders and requests everyday, so as a result it is not always possible for us to keep every item in stock at all times in our warehouse. If you require the item urgently please contact our sales team here to check the stock before you make your purchase.

We totally understand if you're not certain a part will be compatible with your car, so we highly recommend contacting us here with your query. Our friendly sales team will then be in touch to confirm if this part is the correct part you are looking for.

All in stock products ship the same day if ordered before 2pm GMT

For out of stock items we will contact you with an estimated wait time if not otherwise specified above.

We offer worldwide shipping on all products. If upon receiving your product you wish to return; we offer a 30-day returns policy. For our in-depth returns information please follow the link. "R44 Returns Policy

All of our products come with a standard warranty of 1-3 years. This is dependant on the type of product however. For more details please see our warranty page here.