BMW's B58 is the 3.0-litre single-turbo straight six in the M140i, M240i, 340i and M340i, 440i and M440i, 540i, 740i, X3 M40i and X4 M40i, and the Toyota GR Supra. It takes modifications well, but it has been built in several generations, and many upgrade parts are specific to one of them. This guide covers which parts suit which B58, and the order we would fit them in.
If you want to know what "Stage 1" and "Stage 2" mean first, read B58 and S58 tune stages explained. GR Supra owners should also see our GR Supra A90 upgrade guide.
Step 1: Confirm which B58 you have
Charge pipes, downpipes and chillers are made for a particular B58 generation. As a rough guide, earlier F-chassis cars (F20 M140i, F22 M240i, F30 340i, F32 440i) use the first-generation engine, and most G-chassis cars and the GR Supra use the second. Some later facelifted models use the updated B58TU, and 2025-on cars use the newest version.
Step 2: Charge pipes (do these first)
The factory charge pipes are plastic. On a tuned B58 they're a known weak point: more boost means more stress, and a split pipe means lost boost and a tow. Aluminium charge pipes are the first part we recommend on any B58 that is being tuned, or will be.
Project Gamma makes three versions for different B58 engine families. All are aluminium, bolt on, and include the fitting hardware. We match the kit to your engine code before ordering.
BMW B58 Aluminium Charge Pipes$585.00 AUD
BMW B58TU Aluminium Charge Pipes$480.00 AUD
BMW Gen 3 B58 Aluminium Charge Pipes 2025+$681.00 AUD
Step 3: Downpipes (Stage 2)
The downpipe bolts to the turbo outlet and is the biggest restriction left in the exhaust. Project Gamma's B58 downpipes are 4-inch, hand-built from 304 stainless steel, with a CNC-machined v-band at the turbo. Project Gamma keeps the full diameter right up to the turbo rather than necking it down, and quotes gains of around 50 hp once the car is tuned to suit.
Catted or catless
| Option | What it is | Tune needed? | Best for |
|---|---|---|---|
| 200-cell catted downpipe | Keeps a high-flow catalytic converter in the pipe | Yes | Road cars going Stage 2 |
| Catless downpipe (Gen 1 and Gen 2) | No catalytic converter. Polished or ceramic coated | Yes | Dedicated track and competition cars only |
Both need a tune written for them. Without one, expect engine warning lights. The catless version is sold for off-road and sanctioned competition use only. Removing or modifying emissions equipment on a registered road car can breach vehicle standards and affect your insurance, so talk to us about how you use the car before choosing.
BMW B58 and Toyota Supra Catted Downpipe (200 Cell)$1,290.00 AUD
BMW and Toyota Supra B58 Downpipe, Gen 1 and Gen 2From $699.00 AUD
Downpipes are large items, so freight is quoted before you order.
Step 4: Cooling (for summer and track days)
Once the power goes up, heat becomes the limit. Hot intake air means the engine pulls timing and power drops, which is easy to feel on a 40-degree Adelaide day or on the third lap of a track session.
Project Gamma's chiller system for the Gen 1 and Gen 2 B58 connects to the car's factory air-conditioning service ports and uses chilled refrigerant to cool the charge air. Project Gamma says the cabin air-conditioning keeps working normally. You choose the version to match your engine generation and your car's refrigerant (R-134a or R-1234yf), which we confirm during the fitment check. Upgraded heat exchangers are also available. Ask us which suits your car.
Chiller System for BMW B58 (Gen 1 and Gen 2)Intake (540i and 740i)
For the G30 540i and G11/G12 740i (2016 to 2020), Project Gamma makes a carbon fibre intake with a high-flow filter. It's reversible and gives a sharper induction sound. For other B58 models, ask us what's available for your car.
Project Gamma Carbon Fibre Intake: BMW 540i and 740i (B58, 2016 to 2020)The order we'd fit them in
| Step | Parts | Why |
|---|---|---|
| 1 | Aluminium charge pipes and a Stage 1 tune | The best value gain, and it removes the weak point before boost goes up |
| 2 | Downpipes (catted for road cars) and a Stage 2 tune | Faster spool and more top end. Louder |
| 3 | Chiller or heat exchanger | Keeps power consistent in heat and on track |
Common questions
Do I need a tune for charge pipes?
No. They're a direct replacement for the factory pipes. They matter most once the car is tuned, which is why we pair them.
Will a Gen 1 part fit my Gen 2 car?
Sometimes, but not always. The Project Gamma catless downpipe covers both, while chillers come in separate Gen 1 and Gen 2 versions, and the B58TU and 2025-on engines have their own charge pipes. We check this for every order.
How long do parts take?
Most performance parts are ordered in for you and usually dispatch within 1–2 weeks. We confirm the timing when we confirm fitment.
Can you fit them?
Yes. We supply only, or supply and fit at our workshop in Stepney, Adelaide. Fitting and any tune are quoted before we start.
Plan your B58 build
Browse every part for these cars in our BMW B58 parts collection, or send us your VIN, what you use the car for and your budget, and we'll put together a parts list that fits.