Short answer: The S58 has two turbos. On the G80 M3, G82 M4 and G87 M2, each turbo has its own airbox and inlet tube, and a full intake replaces both sides. You do the whole job from the top of the engine bay with hand tools. The strut brace, engine cover and both airboxes come off, then you release the inlet tubes at the turbos. Mishimoto rates its G8X kit at about an hour. Kits that also replace the turbo inlets, like Eventuri's, take longer. The X3 M and X4 M are different. Their factory airbox stays, and most kits swap the four filters and the lid. On stock turbos, an S58 intake is mostly about sound. The steps that matter most are the spring clips and O-rings at the turbo and torquing the strut brace when it goes back on.
Parts in this guide are for off-road / competition use only. Not legal for use on public roads in the United States, including California.
I'm Gleb Blekher. I run B58 Racing out of Dallas, TX. After a tune, an intake is usually the first thing S58 owners ask about. This guide follows the makers' own install instructions. For the G8X cars that's AWE, Mishimoto, Eventuri and Dinan. For the X3 M and X4 M it's Eventuri and Dinan. Where they disagree, or don't say, I'll tell you.
Which intake fits your car
| Car | Chassis | Factory layout | What fits |
|---|---|---|---|
| M3 / M3 Competition | G80 sedan, G81 Touring | Two airboxes, one per turbo | Drop-in filters, carbon lids, inlet pipes, full intakes |
| M4 / M4 Competition | G82 coupe, G83 convertible | Same as the M3 | Same parts as the M3. Check each listing. |
| M2 | G87 coupe | Same S58 layout | Many G8X kits list it. Some list only the M3 and M4. |
| X3 M / X4 M | F97 / F98 | One airbox with four filters | Drop-in filter sets, lid-and-scoop kits, X3 M inlet pipes |
G8X vs F97/F98. X3 M and X4 M intakes don't fit the M2, M3 or M4, and the reverse is true too. Eventuri says its X3 M/X4 M kit fits pre-LCI and LCI cars, using different bracket holes for each.
M2 fitment. AWE, Eventuri, Dinan, do88, MMX and others list the G87 M2. Some Mishimoto and aFe kits list only the M3 and M4. Dinan's G8X instructions are titled for the M3 and M4, though our listing names the M2. Confirm your exact car with us before you order.
The S58 is a different engine from the B58 in the M340i. For that car, read our M340i intake install guide.
The four types of S58 intake upgrade
1. Drop-in filters. Washable filters replace the paper elements in the factory boxes. The G8X cars take a pair. The X3 M and X4 M take a set of four. It's the cheapest, easiest change.
2. Carbon lids with filters. These keep the factory lower boxes and replace the lids. VTT does this for the G8X. On the X3 M, Dinan says the factory intake is efficient for its space and the restriction is the paper filters. Eventuri says the box already has a fairly direct path to the turbos.
3. Turbo inlet pipes. These replace the factory pipes between the airboxes and the turbos. VTT says the factory inlets have accordion sections and internal restrictions. FTP says its aluminum pipes work with the factory airboxes.
4. Full intakes. New boxes, tubes and filters. Some are sealed carbon boxes with extra fresh-air feeds (Eventuri, do88, Mishimoto, Dinan). Others are more open or front-mount designs (AWE, RamAir, Burger Motorsports, Project Gamma). Several also replace one or both turbo inlets.
What an intake actually changes
- Sound. This is the big one. AWE's box even has louvers to aim intake noise at the cabin.
- Power. Small on a stock car. These are the makers' own numbers, so don't compare them directly:
- Eventuri: 13–18 hp and 12–16 lb-ft on the stock tune (G8X V2).
- AWE: up to 14 hp and 9 lb-ft at the wheels, no tune.
- Burger Motorsports: up to 17 wheel hp.
- Mishimoto: up to 22.8% less restriction than stock.
- Dinan: close to 20% more flow than the stock X3 M paper filters.
- Intake air temps. Sealed boxes and scoops are designed to keep engine-bay heat away from the filters. We didn't find an independent back-to-back temperature test we'd trust. Treat "cooler air" as a design goal, not a measured number.
My honest take: on stock turbos, the tune is where the power is. Buy an intake for the sound and the look, or because you're planning bigger turbos. Eventuri says its V2 is built for well over 1,000 hp, and AWE's couplers can come out for bigger turbos later. Our S58 mods guide shows where an intake fits in the order.
Do you need a tune?
In general, no. AWE says the S-FLO needs no tune and backs it with a no-check-engine-light guarantee. Eventuri quotes its gains on the stock tune. FTP says its inlet pipes won't set fault codes. If you're already tuned, tell your tuner what you fitted.
Strut brace fitment
Every G8X kit we read starts by removing the strut braces. Depending on the car, there's one or two. Check that your kit clears yours. Eventuri says its V2 was revised to fit the CSL brace. do88 says its boxes clear the CSL brace. AWE says the S-FLO fits under the Competition Sport (CS) brace.
Which intake to buy: what we sell for S58 cars
Fitment is per our listing, so confirm your exact car before you order. Browse all intakes, or shop everything for the S58.
Drop-in filters and lids (G80, G82, G87)
| Part | Listed for |
|---|---|
| FTP Motorsport High-Flow Air Filters | G80, G82, G87 |
| Dinan High Flow Drop-in Filter Set | G80, G82, G87 |
| RamAir Pleated Filters / RamAir Foam Filters | G80, G82, G87 |
| VTT Drop-In Air Filter | G80, G82 |
| Fabspeed BMC F1 Filters | G80, G82 |
| K&N Replacement Air Filter | G80 |
| aFe Pro 5R Filter / aFe Pro DRY S Filter | G87 |
| VTT Carbon Fiber Intake Kit (carbon lids plus filters) | G80, G82 |
Turbo inlet pipes (G80, G82, G87)
| Inlet | Notes |
|---|---|
| FTP Motorsport S58 Turbo Inlet Pipes | 3 in aluminum. Filters not included. |
| FTP Motorsport Turbo Inlet Pipe (Lite) | Billet, with gaskets in place of small O-rings |
| VTT Silicone Inlet Pipes | Keeps factory-style push fittings at the turbo |
| MMX Intake Pipe Kit | Aluminum, replaces the corrugated factory pipes |
Full intakes (G80, G82, G87)
| Intake | Notes |
|---|---|
| Eventuri Black Carbon Intake V2 | Sealed carbon, new turbo inlets, fits the CSL brace. Optional scoops for the M3/M4 and M2. |
| AWE S-FLO Carbon Intake | Two cone filters in a carbon box |
| Mishimoto Performance Air Intake | M3 and M4. Also an open airbox version. |
| Dinan Carbon Fiber Cold Air Intake | Carbon plenum and lids over the factory lower boxes |
| do88 Intake System | Sealed carbon, extra feeds behind the headlights |
| MMX Carbon Fiber Intake | MMX quotes 49% more filter area |
| Pipercross AirMax | Also sold with a carbon engine cover |
| RamAir High Flow Intake / RamAir Foam Kit with Carbon Lid | Heat shields and machined turbo adapters |
| aFe Momentum GT | M3 and M4, Pro DRY S filters |
| Burger Motorsports Elite Intake | Front-mount. Needs a little plastic trimming. |
| Project Gamma Carbon / Silicone Intakes | Filters included |
X3 M and X4 M (F97/F98)
| Part | Notes |
|---|---|
| Eventuri Black Carbon Intake System | Four filters, carbon lid, two scoops. Replacement filters also listed. |
| Dinan Cold Air Intake (D760-0054) | Drop-in filters plus a carbon lid |
| Dinan Drop-In Filter Set | Filters only |
| FTP Motorsport High-Flow Air Filter | Factory airbox |
| CTS Turbo High-Flow Air Filters | Factory airbox |
| K&N Drop-In Air Filter | Factory airbox |
| FTP Motorsport Turbo Inlet Pipe (Lite) | X3 M/X4 M version |
| Project Gamma Silicone Front Mount Intakes | Silicone front-mount |
My picks:
- Cheapest real change: a drop-in filter pair. Nothing at the turbo changes.
- Most sound with the stock boxes: inlet pipes plus drop-in filters.
- Best heat control on the G8X: a sealed carbon box like the Eventuri V2 or do88.
- X3 M and X4 M: the Eventuri or Dinan kit. Both keep the factory box.
Difficulty, time and tools
- Difficulty: 2 out of 5, or 3 out of 5 for kits that replace the turbo inlets. No lift needed.
- Time: Mishimoto says 1 hour for its G8X kit. The AWE, Eventuri and Dinan instructions we read don't give a time. Drop-in filters are the quickest job. Plan on an afternoon for the Eventuri V2, since you replace both turbo inlets and move the coolant tank.
- Work on a cold car. AWE warns that the exhaust can be very hot.
Tools
These are the sizes the makers list:
- 1/4 in drive ratchet and extensions (Mishimoto). Eventuri suggests a swivel socket and a magnetic socket for the turbo inlet screws.
- 6, 7, 8, 10, 13 and 15 mm sockets (Mishimoto, plus 10 mm for Eventuri's bracket and coolant tank nuts)
- E8 Torx socket for the factory passenger-side turbo snout (Mishimoto)
- T30 Torx for Eventuri's M6 turbo inlet screws, and T25 Torx for the X3 M lid (Dinan)
- 2.5, 3 and 4 mm hex keys (Mishimoto), and a #2 Phillips (Dinan X3 M)
- Pliers and a cloth (Dinan bends two metal tabs for clearance)
- Clean rags for the turbo openings, and a torque wrench for the brace
Torque values
| Fastener | Value | Source |
|---|---|---|
| G8X strut brace nuts | 28 Nm (21 lb-ft) | Mishimoto |
| G8X strut brace bolt | 56 Nm (41 lb-ft) | Mishimoto |
| G8X braces | 28 Nm (20 ft-lbs) | Dinan |
| X3 M / X4 M strut brace bolts (4) | 30 Nm (22 ft-lbs) | Dinan, citing factory spec |
| Hose clamps, sensor screws, carbon hardware | Not given | AWE, Eventuri, Dinan, Mishimoto |
AWE says to check the manufacturer's service manual for exact torque on factory fasteners. None of the instructions we read gives a clamp torque. Eventuri warns more than once that overtightening can damage the carbon. Dinan says its lid screws should only compress the rubber washers slightly.
Step-by-step install: G80 M3, G82 M4 and G87 M2
This is the common sequence from AWE's S-FLO, Mishimoto's MMAI-G80-21, Eventuri's G8X V2 and Dinan's D760-0063 instructions. Your kit's sheet comes first if it differs.
Removing the factory intake
- Take off the strut braces and the engine cover. On some cars the brace hardware is under weatherstripping held by push pins (AWE). The engine cover pulls straight up. Dinan also removes the electronics cover. Keep all the hardware.
- Start with the passenger-side airbox. Loosen the hose clamp where the tube meets the box, and pull the tube off (AWE, Mishimoto).
- Lift the airbox straight up. It sits on three rubber grommets. If any come out with the box, push them back into the car (Mishimoto). The new box uses them.
- Release the tube at the turbo. Pull the locking tab or spring clip out, then pull the tube off the aluminum turbo snout (AWE, Mishimoto, Dinan).
- On the driver side, remove the two plastic push rivets holding the tube to the radiator support. Keep them.
- Unplug the connector your kit shows for clearance. AWE unplugs a fitting under the engine cover by squeezing its tabs. Dinan, Eventuri and Mishimoto each unplug a connector near the driver-side tube.
- Remove the driver-side airbox. Loosen its clamp and lift it off its two grommets. Release the spring clip at the turbo and pull the tube off the plastic turbo snout.
- Cover both turbo openings right away. Dinan says to protect the turbos from debris. Push in a clean rag and leave it until the new parts go on.
Turbo inlet changes (kit-dependent)
This is where kits differ the most.
- AWE: Fit the supplied O-ring and spring clip into each machined coupler. The driver-side coupler is the larger one. AWE says a coupler on the wrong side won't install correctly. The couplers push onto the factory inlets.
- Mishimoto: Remove the two E8 Torx bolts and take the factory aluminum snout off the passenger-side turbo. Fit Mishimoto's snout with the stock hardware. The driver-side plastic snout stays. Mishimoto's CNC adapter pushes onto it. Make sure the spring clip is seated before you press it home.
- Eventuri V2: Both turbo inlets get replaced.
- Unplug the sensor and breather on the inlet, and move a nearby module aside by removing its bracket's 10 mm nut.
- Remove the two screws and lift the inlet out. The breather hose comes out of the engine with it.
- Move the breather assembly and the small metal shim to the new inlet. The shim's notch lines up with the tab inside.
- Start the supplied M6 T30 Torx screws by hand so you don't cross-thread the turbo. Tighten them once both are started.
- On the other inlet, an O-ring sits inside the lower screw hole. Make sure it stays there.
- Dinan: The factory inlet tubes stay. Bend the two metal tabs Dinan shows using pliers and a cloth. Dinan's rubber hoses snap over the front lip of the factory inlets. The longer hose goes to the rear turbo, the shorter to the front.
Fitting the new intake
- Build each side on the bench. Fit the mounting posts or pegs to the boxes, then assemble the tube, coupler and filter and tighten the filter clamps (AWE, Mishimoto). Mishimoto says to seat the rubber grommet lip all the way around the airbox lip.
- Protect the carbon. Eventuri covers some metal tabs with a cloth before lowering its carbon tube in. Dinan puts a rag over a metal panel.
- Fit the passenger side. Lower the tube end in first, line it up with the turbo coupler, then press the box onto its three mounts. AWE says that if the coupler won't connect, the spring clip may be touching the factory heat shield. Rotate the coupler until it presses in.
- Fit the driver side. AWE says the gap between the engine and the tube is tight but it fits. Connect it at the turbo and press the box onto its two mounts.
- Eventuri V2: one housing needs extra room. Remove the two 10 mm nuts on the coolant tank bracket and lift the tank out of its white rubber mount. Nothing gets drained. Lower the housing past the turbo actuator. Eventuri labels its sides RHS and LHS, so follow its photos.
- Tighten the remaining clamps once everything lines up. Mishimoto and Dinan tighten one clamp per joint first and finish the other once the box is seated. Dinan fits the braces before the final clamp tightening, because the brace fully seats its plenum.
- Refit the push rivets and brackets. Mishimoto adds two brackets on the driver-side tube that clip to the radiator support with the factory pop clips.
- Reconnect everything you unplugged. On the Eventuri, set the coolant tank back into its grommet and refit the two 10 mm nuts.
- Refit the engine cover and braces, and torque the brace. Mishimoto gives 28 Nm (21 lb-ft) for the brace nuts and 56 Nm (41 lb-ft) for the bolt. Dinan gives 28 Nm (20 ft-lbs).
AWE does one thing differently. It has you drive the car before refitting the braces, let the bay cool, check the intake alignment, and then put the braces back.
Step-by-step install: X3 M and X4 M
This follows Dinan's D760-0054 and Eventuri's X3 M/X4 M instructions.
- Remove the engine compartment covers on both sides (Dinan).
- Fold back the hood seal mounts. Remove the expanding rivets and fold the seal aside (Dinan). Keep the rivets.
- Remove the strut brace. The nuts are under rubber end covers, two per side (Eventuri). Dinan uses a 15 mm socket.
- Take off the airbox lid. Dinan uses a T25 Torx bit.
- Remove the filters. Each sits under a plastic frame held by clips. Press the middle of each clip to lift it, then remove the frame and filter. Dinan's set has two small and two large filters. Eventuri says that if there are grey charcoal filters behind the paper ones, you may remove them too.
- Fit the new filters, fully seated, then refit the frames and clips.
- Fit the new lid.
- Eventuri: Move the M badge to the carbon lid by carefully bending back its tabs. Fit the lid with the supplied plastic washers and factory screws.
- Dinan: Thread the magnet standoffs in slowly with a #2 Phillips. They go into plastic, so snug only. Leave a small gap between magnet and standoff. The lid then clicks onto the magnets.
- Refit the strut brace. Dinan gives 30 Nm (22 ft-lbs) for the four bolts. Then refit the hood seal rivets and engine covers.
- Eventuri scoops. Remove the front grilles over the air ducts and bolt each scoop to its bracket. Non-LCI cars use the upper holes and LCI cars the lower ones. Clip the bracket onto the strut brace, seat the scoop clips in the duct, and check that the inner duct panel is held by the scoop clips. Refit the grilles.
Checks after the install
- Look over every clamp, plug, breather and push rivet before you start the car.
- Count your rags out and back in.
- Listen for whistles or hissing at idle.
- If you get a check engine light, AWE says to make sure every hose is reinstalled and secure.
- After the first drive, let it cool and recheck clamps and alignment.
- AWE says to inspect its filters every 25,000 miles and clean them every 50,000, sooner in dust. Burger says every 15,000 to 20,000 miles for its filters.
Common mistakes
- Dropping something into a turbo. Cover both openings as soon as they're open.
- Spring clip not seated. The tube can pop off under boost. Tug on each connection after fitting it.
- Lost or pinched O-rings. AWE's couplers use side-specific O-rings. Eventuri warns about the one in the lower screw hole.
- Mixing up sides. AWE's couplers are different sizes. Mishimoto uses a smaller filter and grommet on the passenger side.
- Cross-threading the turbo. Start screws by hand.
- Losing the rubber grommets. The new boxes press onto them.
- Overtightening clamps on carbon. Eventuri and Dinan both warn against it.
- Forgetting a plug. Several kits unplug a connector for clearance.
- Skipping the brace torque. It's a structural part.
- Buying the G8X kit for an X3 M. They don't interchange.
FAQ
What is the best intake for the S58?
For heat control, a sealed carbon box like the Eventuri V2 or do88. For sound, AWE's S-FLO is built around it. On a budget, drop-in filters or inlet pipes keep the factory boxes. On the X3 M and X4 M, Eventuri and Dinan upgrade the filters and lid.
How much horsepower does an S58 intake add?
Not much on stock turbos. Claims include 13–18 hp from Eventuri on the stock tune, up to 14 wheel hp from AWE, and up to 17 wheel hp from Burger Motorsports. Each maker tests differently.
How long does an S58 intake install take?
Mishimoto rates its G8X kit at 1 hour. Drop-in filters are quicker. Kits that replace both turbo inlets, like the Eventuri V2, take longer.
Do I need a tune after installing an intake on my M3 or M4?
Usually not. AWE says no tune is required, and Eventuri quotes its gains on the stock tune. If you're already tuned, tell your tuner.
What is the S58 strut brace torque?
Mishimoto's G8X instructions give 28 Nm (21 lb-ft) for the brace nuts and 56 Nm (41 lb-ft) for the bolt. Dinan's G8X instructions give 28 Nm (20 ft-lbs). Dinan's X3 M/X4 M instructions give 30 Nm (22 ft-lbs).
Will my intake fit with the CSL or CS strut brace?
Eventuri's V2 and do88 say they clear the CSL brace. AWE says the S-FLO fits under the CS brace. Check other listings.
Is the install different on xDrive cars?
We found no maker instructions with xDrive-specific steps. All the work is from the top.
Do I have to drain coolant?
None of the intake instructions we read drain coolant. Eventuri's V2 has you lift the coolant tank aside, but the system stays closed.
Planning your next step? Start with our S58 mods guide. Doing more under the hood? See the S58 charge pipe install and the S58 downpipe install.
Sources
- AWE S-FLO steps, couplers and O-rings, heat shield clearance, drive-then-refit braces, filter intervals, service manual torque note: AWE 2660-15489 installation instructions, Rev 1.1
- Mishimoto steps, tools, 1 hour time, E8 Torx turbo snout, grommets, brackets, brace torque of 28 Nm and 56 Nm: Mishimoto MMAI-G80-21 installation guide
- Eventuri G8X steps (turbo inlet swap, metal shim, breather, T30 screws, O-ring in the screw hole, coolant tank, don't overtighten carbon): Eventuri EVE-G8XMV2-CF-INT installation instructions
- Dinan G8X steps (electronics cover, protect turbos from debris, bending tabs, hose lengths, rubber washers, brace torque of 28 Nm): Dinan D760-0063 installation instructions
- Dinan X3 M/X4 M steps, tools, hood seal rivets, magnet lid, brace torque of 30 Nm: Dinan D760-0054 installation instructions
- Eventuri X3 M/X4 M steps (brace nuts, filter frames, charcoal filters, badge, LCI and non-LCI scoop holes): Eventuri X3M/X4M installation guide
- Maker power and flow claims (Eventuri, AWE, Burger, Mishimoto, Dinan, MMX), strut brace fitment (Eventuri, AWE, do88), FTP fault-code note, VTT design notes, Burger trimming and filter interval: manufacturer product information on our listings