Get the latest tutorials and stories!

G80 M3 BMC filters

G80 M3 BMC air filter DIY and review

I’ve modified nearly every car I’ve ever owned, and my G80 will be no exception. For starters, I’ll install a BMC air filter in the stock G80 air boxes. Is it hard? No. Is it worth it? Well…

Before you begin

You’ll need some things:

  • BMC high-flow air filters (I got mine from AutoCouture, because those guys are awesome and they won’t steer you wrong on this platform).
  • A flat-head screw driver
  • 13mm & 16mm Wrench (socket)
  • T25 Torx driver

How hard is this to do?

If you feel uncomfortable installing this on your own, you probably shouldn’t be working on a car, because it’s as easy as it gets.

G80 M3 engine bay
If you’ve ever owned an M3, opening the hood is probably second nature to you by now.

DIY Step 1: Strut Tower Brace removal

Remove the front strut tower brace. The rear bolts are 13mm, and the front one is 16mm. Then, lift the bar up and set it in a soft place so it does not get scratched.

G80 engine bay
Removal of the front brace is quick.
G80 M3 strut brace
This guy was a bit stuck on. Make sure you tighten back up to spec, 18 lb-ft.

Step 2: Air Box removal

Take your Torx driver and unscrew one air box at a time. The screws are designed to stay in place on the air box, so you don’t need to take them all the way out. You’ll feel the screw release the bottom half of the air box, and that’s when it’s time to stop turning.

Next, take a flat-head screw driver and unscrew the intake tube. Pull the top half of the air box out. Repeat for the other side of the car.

G80 M3 airbox
These air box screws are designed to stay in after you unscrew them, meaning you won’t lose them. Yay German engineering.
G80 M3 airbox
Just unscrew the clamp and tug the box out.
G80 M3 airbox
It’s not impossible to remove the airbox with the strut bar installed, but it’s much easier to do it with it off.

Step 3: Charcoal Filters removal

Ahh, the charcoal filters.You can grab them at the bottom and tug. They fold like an accordion and come out easily enough.

G80 M3 airbox
The charcoal filters are in the top of the air box, and folding them like an accordion makes them pop out easily enough.

Step 4: New filters

Take out the old air filters, and pop in your BMC air filters. Then reverse the steps. You’re done.

G80 BMC air filter
The BMC air filters are a direct replacement, and fit is easy.
BMW air filter
The old filters are labeled with an “M”, though they look like every other stock BMW air filter.
G80 air box
Just repeat the process on the other side, then put the brace back.
G80 M3 air box
Adding the sticker can’t hurt, you don’t want the dealer throwing them away.
G80 M3 engine bay
All done! This took about 20 minutes.

Q&A: Will removing just the charcoal filters make a difference?

If you’re interested in the science, this video explains if taking the charcoal filter out improves engine power and response. In short, it does, but by a small amount.

Are oiled filters a rip-off?

I’ve used them on every single car I’ve owned, from my 3000GT, 350Zs, E92 M3, etc. I used to go to K&N, but this BMC air filter comes highly rated, and the principals are the same. I’ve never had any issues with warranty, clogged throttle bodies, or rough idles.

Are BMC filters make a difference?

BMC claims that they add 10 horsepower to the G80, and have provided a dyno result with an F82 M4 as proof. They have yet to test a G80, but let’s say it is in fact 10 hp.

On a car that makes 473 horsepower, adding 10 amounts to a 2 percent difference in power. You won’t feel it.

Should I get a full intake system on my M3 instead?

Debatable, but for me, that’s a no dog. Take a look at the stock air box – BMW knows what it’s doing. Each side features a cold-air tube that leads to the front of the grill. The boxes themselves are well insulated and sealed nicely. Adding a cone filter and new tube will give you a louder turbo woosh sound, but performance improvements are minimal. We don’t want to be sucking in hot air from the engine bay.

Did you feel a difference?

Yes! I did not notice more power (2 percent…), but the car does have a smoother rev to redline, and feels like it revs faster.

Also remember that mods work together. Adding an intake and exhaust together will yield a greater result, and so on.

Do you recommend the BMC air filter kit for the G80?

For $180 at ACM, it’s a cheap and easy mod that makes the M3 a bit more enjoyable to drive. Now, onto picking an exhaust…

G80 M3 front
I will never complain about more power, even if it’s just 2 percent.

Commissions may be received for product links on this site, so help out if you can. I only write about products I use and believe in.

I use Nikon camera bodies and lenses, a Westcott Ice Light 2, Manfrotto tripod, B + W filters and an iMac Pro to make the art you see here.

Email me at mike@machineswithsouls.com with any questions.

Follow along on Instagram @machineswithsouls

Legal

Due to factors beyond the control of Machines With Souls LLC and Mike D’Ambrosio, I cannot guarantee against improper use or unauthorized modifications of this information. Machines With Souls LLC and Mike D’Ambrosio assumes no liability for property damage or injury incurred as a result of any of the information contained in this post. Use this information at your own risk. Machines With Souls LLC and Mike D’Ambrosio recommends safe practices when working on vehicles and or with tools seen or implied in this post.

Due to factors beyond the control of Machines With Souls LLC and Mike D’Ambrosio, no information contained in this post shall create any expressed or implied warranty or guarantee of any particular result. Any injury, damage, or loss that may result from improper use of these tools, equipment, or from the information contained in this post is the sole responsibility of the user and not Machines With Souls LLC or Mike D’Ambrosio.

Leave a Reply

Your email address will not be published. Required fields are marked *