BMW E46 Turbo Guide: Parts List and Installation
Building a turbo E46? Start with the parts you actually need, then install them in the right order. This guide covers budget and premium options, blow-through MAF placement, fuel upgrades and exactly where the turbo oil returns.
The main parts list is for M52TU/M54 cars. The E46 M3 uses the S54 and needs its own manifold, intake and tuning setup; see the M3 section below.
Before buying: know your engine, ECU, fuel and power goal. M52TU cars use MS42; M54 cars use MS43 or MS45.1. If needed, use our ECU identification guide. Fix overheating, misfires, oil-pressure problems and intake leaks before adding boost.
Jump to the part you need
1. M52TU/M54 parts shopping list
These are named parts and buying options, not one universal bolt-on kit. Choose a hot-side combination first: its turbo flange, wastegate connection and downpipe outlet must match. The CXRacing examples below are for non-M E46s; xi and right-hand-drive cars need a kit specifically confirmed for that layout.
| Part | Budget route | Upgrade route |
|---|---|---|
| Turbo | Used genuine Holset HX35/HX40 or a Maxpeedingrods GT35-style turbo. | Garrett GTX3071R / G30-660 for a smaller street setup; GTX3582R / Precision 6266 for a larger build. |
| Manifold + downpipe | CXRacing MF-DP-BMW-E46-TOP: T3 top-mount manifold and matching downpipe. Its turbo connection is a 2.5-inch four-bolt outlet. | Fabricated M52TU/M54 E46 manifold and downpipe built around your exact turbo. Specify T3, T4 or V-band before ordering. |
| Wastegate | The 38 mm gate supplied with the CXRacing TRB-KIT-BMW-E46-GT35-IC-KIT. The manifold/downpipe-only package above does not include a gate. | TiAL MVR 44 mm: use a manifold with its matching V-band flange, or budget for welding the supplied flange. |
| Intercooler + piping | CXRacing E46 piping/intercooler package or a universal core with DIY aluminum pipes. | Treadstone TR8L with fabricated brackets and piping. Measure the bumper opening and space behind it. |
| MAF | Genuine Hitachi 22680-7S000 / MAF0031 or Audi RS4 Bosch 0280218067. | PMAS MH30-HPX, MH30-HPXE or MH35-HPXE. All options go in the charge pipe after the intercooler. |
| Injectors | Genuine, flow-tested Bosch 0280158123 for a suitable smaller combination. | Matched FIC 1000/1650 or Injector Dynamics ID1050-XDS / ID1300-XDS, sized for your fuel and output. |
| Fuel pump | DW300 BMW kit 9-301-1031. Check the listed model/year. | DW400 BMW kit 9-401-1052 with suitable wiring; larger builds may need more pump capacity. |
| Oil feed | RallyRoad VANOS banjo oil supply fitting and a -4AN feed line. | RallyRoad Turbo Oil Distribution Gauge Block at the oil-filter housing, with a -4AN line. |
| Oil return | Turbo drain adapter, -10AN hose and bung in the upper oil-pan sidewall or a timing-cover return fitting. | For a low turbo: TurboWerx Exa-Pump and return plumbing to the dipstick return, timing cover or oil pan. |
| Blow-off valve | Valve and matching flange supplied with your piping kit. | A genuine TiAL Q or Turbosmart RacePort with its matching flange. Install before the MAF. |
| Wideband | AEM X-Series 30-0300 gauge/controller and exhaust sensor bung. | The same wideband, plus fuel-pressure and oil-pressure monitoring. |
| Finishing parts | Reinforced couplers, T-bolt clamps, vacuum hose, catch can, heat shields, exhaust supports, gaskets, studs and fittings. | Clutch matched to torque, repaired/reinforced rear subframe mounting area, and oil/cooling upgrades for repeated hard use. |
Budget tip: the complete CXRacing kit gives you a named starting package for the turbo, manifold, wastegate, downpipe and charge piping. It still needs fuel upgrades, the blow-through MAF setup, tuning and the exhaust after the downpipe. Budget for fitting and fabrication.
2. Turbo, manifold, wastegate and downpipe
Turbo: buy for the car you want to drive
A used Holset or a budget GT35-style turbo keeps the initial cost down. Check condition, oil requirements and the actual turbine housing. “GT35” on a listing does not make every turbo the same.
For a responsive street build, look at a GTX3071R or G30-660. A GTX3582R or Precision 6266 makes more sense when you are building the engine and supporting systems for more output. A bigger turbo usually brings more lag. Choose the manifold and downpipe to match the turbo you buy.
Manifold: top mount or bottom mount
Top mount gives easier turbo access and usually makes a downhill oil drain easier. Bottom mount keeps the turbo lower but can require a scavenge pump and tighter downpipe fabrication.
Budget cast manifolds and CXRacing/eBay tubular manifolds can work, but test-fit them before final assembly. Inspect welds and flange flatness; repair weak areas and support the turbo/downpipe. Confirm room around the steering shaft, engine mount, A/C lines and hood.
Wastegate: match the flange and control the boost
The CXRacing package uses a 38 mm gate. A TiAL MVR is a 44 mm V-band gate, so it needs its own flange rather than being bolted onto the kit's 38 mm connection. Choose the spring with your tuner before installation. Connect the pressure line using the gate's instructions and check boost at spring pressure first.
Downpipe: match the turbo outlet
The MF-DP-BMW-E46-TOP downpipe is for a four-bolt turbo outlet. A V-band turbo needs a matching downpipe or a fabricated outlet change. Run a supported 3-inch exhaust as a practical starting point for many builds, leave room for engine movement, and shield nearby wiring and brake components from heat.
3. MAF options: blow-through only
Poverty Built turbo setups covered here use an upgraded MAF in blow-through placement. The factory BMW MAF is not a supported turbo option. Choose Hitachi, Audi RS4, HPX or HPX-E and have the tune match that sensor and housing.
| MAF | Part number / kit | What to buy |
|---|---|---|
| Hitachi / Nissan |
22680-7S000 Hitachi replacement: MAF0031 |
Budget option. Buy a genuine sensor, matching connector and a sealed housing for the charge pipe. |
| Audi RS4 |
Bosch 0280218067 Connector: 1J0973775A |
Buy this specific sensor version. Include its housing size in the tune order; a different RS4-branded replacement is not automatically interchangeable. |
| PMAS HPX | MH30-HPX | HPX sensor with a 3-inch blow-through housing. Order the matching pigtail. |
| PMAS HPX-E | MH30-HPXE / MH35-HPXE | Extended-range sensor with a 3-inch or 3.5-inch blow-through housing. Choose the housing before ordering the tune. |
Placement: install the MAF in the cold-side charge pipe after the intercooler and before the throttle body. Put the blow-off valve upstream of the MAF. The valve releases air before it gets measured.
BOV branches off hereMAF in straight pipeThrottle bodyEngine
Give the MAF a straight pipe section on both sides, away from bends, reducers and the BOV outlet. Seal its mounting flange and pressure-test the finished piping. Keep the sensor's airflow arrow pointing toward the engine. Wire the matching connector for the selected sensor and ECU before first start.
4. Injectors and fuel pump
Buy a matched set of six genuine injectors and give us the part number when ordering. The Bosch 0280158123 is a budget option for the right combination; FIC and Injector Dynamics offer larger matched sets. Pick the size around your fuel and target, with room to spare.
| Target engine horsepower | Gasoline: injector size to shop for | E85: injector size to shop for |
|---|---|---|
| 350 hp | 550 cc/min or larger | 650 cc/min or larger |
| 500 hp | 750 cc/min or larger | 1,000 cc/min or larger |
| 650 hp | 1,000 cc/min or larger | 1,300 cc/min or larger |
| 800 hp | 1,300 cc/min or larger | 1,650 cc/min or larger |
These are rounded planning sizes for six injectors rated at 3 bar, with a fuel system that maintains pressure across the injector under boost. They use engine horsepower, not wheel horsepower. A fixed-pressure setup can need larger injectors. Choose the final size with the tune before buying.
A DW300 9-301-1031 or DW400 9-401-1052 is a concrete pump option. Use suitable fused relay wiring, ethanol-compatible in-tank hose when running E85, and keep the tank's transfer plumbing working. Check fuel pressure under load.
The M54 has its regulator at the fuel filter. If you add a return system, use a 1:1 boost-referenced regulator, feed/return plumbing and a tune set up for it. Tell us the base pressure and whether the regulator is boost-referenced. Raising pressure alone is not a fuel-system upgrade.
5. Oil feed and exactly where the return goes
Oil feed
Use the RallyRoad VANOS banjo fitting at the VANOS oil-line connection, or its Turbo Oil Distribution Gauge Block at the oil-filter housing. Run a -4AN feed to the turbo. Use the restrictor specified for your turbo; journal-bearing and ball-bearing units can have different requirements.
Gravity return: oil pan or timing cover
For a turbo mounted high enough to drain downhill, run the drain to a -10AN bung in the upper sidewall of the oil pan or a dedicated timing-cover return fitting. Put the return opening above the normal oil level, with clearance inside the engine. Keep the hose continuously downhill, without dips or tight bends. Remove and clean the pan or cover when machining or welding it.
Low-mounted turbo: scavenge pump
If the turbo sits too low for a downhill drain, use a turbo oil scavenge pump, such as the TurboWerx Exa-Pump. Run the turbo drain to the pump's collection arrangement, then pump the oil back through a dedicated dipstick-tube return adapter, timing-cover fitting or oil-pan bung. New cover/pan return fittings go above the normal oil level. Keep the dipstick guide clear and separate the return from the old CCV plumbing.
High-mounted turbo: turbo drain → downhill -10AN hose → upper oil-pan bung or timing-cover fitting.
Low-mounted turbo: turbo drain → collection arrangement → scavenge pump → dipstick return adapter, timing cover or oil pan.
Follow the pump's mounting and wiring instructions. Protect oil lines from exhaust heat. If the turbo or wastegate uses coolant, plumb those connections to the component's instructions during the same installation.
6. Supporting parts worth spending money on
- Intercooler and piping: mount the core in airflow, bead-roll pipe ends, use reinforced couplers and pressure-test the entire intake. Keep the healthy factory intake manifold and cams for a straightforward street build.
- Crankcase ventilation: replace the stock CCV arrangement with a properly plumbed catch-can system for boost. Prevent intake boost from pressurizing the crankcase. Check the DISA seal and idle-air hoses for leaks.
- Vacuum lines: the BOV and a boost-referenced fuel regulator need manifold pressure after the throttle. Route the wastegate separately to its instructions. Keep the brake-booster check valve working.
- Head sealing: when the build calls for studs or a different gasket, check the aluminum block's threads and deck. An MLS gasket needs the specified surface finish; a cut-ring gasket needs its own machining and installation. Include that work in the budget.
- M54 oil pump: for repeated high-rpm use, address the shaft, sprocket retention and chain. The Hopwood M52TU/M54 billet oil-pump upgrade is a named option.
- Clutch and chassis: choose the clutch by torque and gearbox fitment. Inspect the rear subframe mounting area for cracks, repair damage and reinforce where needed. Check the differential mounts, flex disc and driveshaft support.
Where to save: DIY piping, brackets, exhaust fabrication and healthy stock intake/cam parts. Where to spend: fuel delivery, wastegate, oil return, cooling, clutch, structural repairs and tuning. Stock-engine condition and torque delivery matter; no horsepower number guarantees that an old engine will stay together.
7. E46 M3 / S54: use S54 parts
The M3 needs an S54-specific turbo manifold, downpipe and pressurized intake plenum for its individual throttle bodies. The M52TU/M54 CXRacing package above does not fit it. Keep the S54 injector, oiling and MSS54 tuning requirements separate from the non-M parts list.
Check bearing-service history, VANOS, cooling and the rear subframe mounting area before the conversion. Plan the full hardware and tune together before buying an S54 turbo kit.
8. Before first start and ordering a tune
- Record the engine and ECU, turbo model, wastegate spring, MAF part number/housing size, injector part number, fuel pump, fuel type and base fuel pressure.
- Have the correct turbo tune ready. Pressure-test the intake, check fuel joints, prime the turbo and verify the oil-return path before starting.
- At first start, check oil pressure, fuel pressure, wideband readings, temperatures and leaks. Fix problems before loading the engine.
- Begin at the agreed wastegate spring pressure and follow the tune's logging instructions. Stop for fuel-pressure loss, uncontrolled boost, overheating or misfires.
For a listed combination, choose the matching MS43 preset forced-induction tune. The parts in this guide do not automatically form a preset: the installed MAF, injectors and fuel must match the product's offered combination. For other builds, use the MS42, MS43 or MS45 forced-induction tuning page to find the appropriate service.
Send the actual parts list when ordering. That lets us match the tune to the car you built.