CSL Front Bumper Ducting

[BMWahba]

Hello all,

The time is near when I finally install my CSL Bumper from MileEnd I've been sitting on for a few years.

I was curious if anyone here has done and replicated the factory CSL bumper ductwork. I actually have all of the parts minus the flexible hose part #13717896774.



The parts I do have:

"Intake Tube" - 1617833648
https://www.ecstuning.com/b-genuine-...617833648~geb/


Air Intake Hose - 11617833646
https://www.ecstuning.com/b-genuine-...617833646~oee/

BMW Suction Tube - 11617833645

https://www.ecstuning.com/b-genuine-...617833645~oee/




It's pretty unclear exactly how these parts are configured and snaked through the front ducting area and was looking to get some help to make sure I'm not missing anything I haven't thought of.

Can anyone offer any insight or possibly have some photographs of it in detail? I plan on replacing the flexible ducting with brake ducting potentially, but I'm not really sure.

[Cubieman]

I had a photograph (I think from cslregister) from the perspective of the backside of the bumper with the bumper off the car and it is was quite clear how it all came together, I'll keep looking.

[BMWahba]

I had a photograph (I think from cslregister) from the perspective of the backside of the bumper with the bumper off the car and it is was quite clear how it all came together, I'll keep looking.

That's an interesting diagram there. Thanks for sharing. That one does indicate where the 3 pieces I do have go, but what's alluding me is what the flexible hose does and how it fits into all of that. It's not even shown in this photo. Seems it likely feeds that lower air hole on the bottom side where it joins with the intake pipe #3.

Would love to see that photo you mention!

[Slideways]

m3dragon has the complete ducting on the CSL clone build:

https://e46m3.bimmerpost.com/forums/...=715028&page=7

[Cubieman]

I'll keep looking but browse this entire thread:

https://forums.m3cutters.co.uk/threads/oem-csl-intake-install-evolve-alpha-n-tune-project.33785/

[heinzboehmer]

Those diagrams are from the CSL aftersales training document. I've attached it here. Pages 25-30 describe the intake system.

The bendy duct just acts as a muffler. It's not entirely necessary to have, as its only purpose is to muffle intake noise at low rpm. The other parts are more important, as they funnel cold air to the intake.

This thread also has some good pics showing how the ducting goes: https://nam3forum.com/forums/forum/m...5610#post15610

[Cubieman]

Those diagrams are from the CSL aftersales training document. I've attached it here. Pages 25-30 describe the intake system.

The bendy duct just acts as a muffler. It's not entirely necessary to have, as its only purpose is to muffle intake noise at low rpm. The other parts are more important, as they funnel cold air to the intake.

This thread also has some good pics showing how the ducting goes: https://nam3forum.com/forums/forum/m...5610#post15610

Ha, that was my thread and 0-60's photo I was searching for.

[BMWahba]

Those diagrams are from the CSL aftersales training document. I've attached it here. Pages 25-30 describe the intake system.

The bendy duct just acts as a muffler. It's not entirely necessary to have, as its only purpose is to muffle intake noise at low rpm. The other parts are more important, as they funnel cold air to the intake.

This thread also has some good pics showing how the ducting goes: https://nam3forum.com/forums/forum/m...5610#post15610

Really interesting. Kind of strange how that flexible hose just kind of hangs there. The narrow portion just tucking into the bumper by the hole. So safe to say I can kind of skip that....

[heinzboehmer]

Really interesting. Kind of strange how that flexible hose just kind of hangs there. The narrow portion just tucking into the bumper by the hole. So safe to say I can kind of skip that....

Yep, doesn't really serve a purpose besides muffling

[duracellttu]

I reached out to some OEM CSL owners a while back to figure out the same thing. Here is what I found.

A few things to note. You will need hold drilled near the bumper intake holder to mount the plastic end of the foam noise suppression hose. Miles End did t drill these holes if I recall correctly, or even have a place to mount that piece. I tried to work with Mike End pre-pandemic to get this designed but I don’t think his product was ever updated.

Also, mounting studs on the frame didn’t come standard with US M3s. Some welded them on, others have drilled through the entire bumper mount to get a bolt through.

Last, you will need to cut away a section of the sliver metal mount that holds the diaper so you can route one of the tubes through. There is a CSL specific part number for this but if I recall it was a bit pricey.

Hope these pictures help.