Karbonius CF reproduction of standard S54 plenum **PROTOTYPE VIDEO**

[mchart]

I do worry about that amount of flex over time, and the thing staying sealed.

[MBan]

Originally Posted by maupineda

I am in!

One thing to note is that under load, the prototype box deflects, would you ask if they can fix that?

I'll ask. I do wonder if reducing the flex will reduce the sound, but I'm interested to hear Karbonius's thoughts.

[maupineda]

Maybe they can use the support the CSL has

[MBan]

Does your CSL intake have extra bracing in that part?

The CSL intake has pretty much no restriction after the filter element, so maybe the OE airbox and MAF create more of a restriction and more vacuum in the plenum?

[mchart]

Originally Posted by MBan

I'll ask. I do wonder if reducing the flex will reduce the sound, but I'm interested to hear Karbonius's thoughts.

I doubt it. I guess I shouldn't have been so surprised to see how much the sound muffling is just due to the stock airbox after the plenum itself.

Problem is finding a good intake for a Z3M these days isn't easy.

[MBan]

Okay, so I have a couple of questions to ask Karbonius:
- can the plenum be strengthened so it doesn't flex so much?
- which rubber boots were used in the design (my understanding is that Z4Ms and post-2004 E46 M3s have one type of boot (part number 11617835861) and pre-2004 M3s and M3 CSLs have another kind (part number 11612466477) and they're not interchangeable. This also means the OE clips on the plenum side are different - Z4M is 11617835320 and pre-2004 M3/CLS is 11617830306)

Before I go back to Karbonius I want to check if anyone else has questions or comments?

E86Z4MC grannyknot AK72 86Zed wdb drivetolive pwnsweet alfadog TurboDream17 zed_fan sgrg GuggagZ4M RvsBmw Barryb97 ZeD4Mr Mtxzptlk Kuky Jdmaflac krohn27 Polarbert flipjohannon

[grannyknot]

The Karbonius logo seems to be under a layer of clear coat so not removable, will they also have a version with no advertising on on it?

[MBan]

Originally Posted by grannyknot

The Karbonius logo seems to be under a layer of clear coat so not removable, will they also have a version with no advertising on on it?

I will check - thanks.

[Jdmaflac]

Originally Posted by MBan

Okay, so I have a couple of questions to ask Karbonius:
- can the plenum be strengthened so it doesn't flex so much?
- which rubber boots were used in the design (my understanding is that Z4Ms and post-2004 E46 M3s have one type of boot (part number 11617835861) and pre-2004 M3s and M3 CSLs have another kind (part number 11612466477) and they're not interchangeable. This also means the OE clips on the plenum side are different - Z4M is 11617835320 and pre-2004 M3/CLS is 11617830306)

Before I go back to Karbonius I want to check if anyone else has questions or comments?

E86Z4MC grannyknot AK72 86Zed wdb drivetolive pwnsweet alfadog TurboDream17 zed_fan sgrg GuggagZ4M RvsBmw Barryb97 ZeD4Mr Mtxzptlk Kuky Jdmaflac krohn27 Polarbert flipjohannon

For me at least, my only concern is the flex. Didn't know if a brace is the solution or if additional cf plies are needed. And if that is the case, what is the added cost? I'm sure they will address this in their 2nd revision.

[RvsBmw]

Originally Posted by MBan

Before I go back to Karbonius I want to check if anyone else has questions or comments?

Would you ask if they will make an elbow + airbox (front part) or if they are willing to think about? Don't want too buy an eventuri kit too (don't have one atm). They make that for the e9x v8 too:

Thanks for asking.

[MBan]

Originally Posted by Jdmaflac

For me at least, my only concern is the flex. Didn't know if a brace is the solution or if additional cf plies are needed. And if that is the case, what is the added cost? I'm sure they will address this in their 2nd revision.

Thanks - I've sent that as one of the questions.

RvsBmw - Not to put words in their mouth, but I would imagine they could be willing if there was enough interest. Getting enough interest would mean going down the same path as we have for plenum. I'll float the idea with Karbonius.

[maupineda]

It would be more expensive than the eventuri. I would not be interested

[MBan]

Originally Posted by RvsBmw

Would you ask if they will make an elbow + airbox (front part) or if they are willing to think about? Don't want too buy an eventuri kit too (don't have one atm). They make that for the e9x v8 too:

Thanks for asking.

I checked on realoem and the E46 part numbers are different from the Z4 part numbers. I imagine that if Karbonius were to make a CF version of the airbox and elbow, it would be for the M3, not for us Z4ers. I have asked anyway and will let you know what they say.

They have come back with responses to my other questions:

Q. There appears to be quite a lot of flex in the top of the plenum. People have expressed concern that this could result in the unit failing over time, probably where the two parts are bonded together. Is there a way to strengthen the top? Or do you think this isn't needed?

A. Yes, a lot of flex on the top, this is because this unit was made without the inner pilar reinforcement, we are installing a inner reinforcement ( like the ones we are using in the CSL airbox) and we will test again, I hope not to loose too much sound!! Anyway ,I´m not worried about the union between 2 pieces, I´m sure will not fail on this area, we are using a very good glue, it support a lot of cicles of flexion and traction

Q. Is it possible to order the plenum without any logo or writing on the top?

A. Yes , no problem, we could send it with the Mpower sticker separately ( not glued under the varnish)

I also asked about the rubber coupling and they advised that their plenum is designed to work with part number 11617830265. This is part from the CSL and pre-2004 M3.
https://www.realoem.com/bmw/enUS/par...&q=11617830265

Can anyone confirm if Z4 and post-2004 M3 rubber couplings work with the CSL airbox? I have never read that they DON'T, but would like to confirm as the rubber boots are quite expensive.

[Vanne]

Originally Posted by MBan

Karbonius has test-fitted the plenum and made a video, as well as videos of the same car with a completely stock intake and the same car with their CSL-style intake. I've posted the videos below. Karbonius are on holiday until 30 August but provided a few comments when they sent me the videos:

"I just sent you 3 videos,
1- OEM airbox, you can see the results in dB , minimum 72,2 and maximum at 5000 rpm 106 dB
2- CSL airbox , minimum 79 , maximum at 5000 rpm 130.2 dB
3 -Karbonius OEM style airbox, minimum 74,3 , maximum at 5000 rpm 118,7 db.

Sorry for the quality of the video, maybe doesn't´do justice comparing with real sound, but I think you can hear the difference between the 3 boxes.
We have 2 dB more in the low measure and +12,7 dB in the revolutioned measurement . The Karbonius OEm style airbox is not as louder as the CSL airbox, but clearly louder than the OEM one.
We checked on the car and drove few kilometers, and we could hear clear the sound of the box, specially between 2500 to 4000 rpm, driving at few rpm and putting gas in 4th or 5th gear is easy to heard."

I also asked a couple of questions:
Q. Will the price be the same as originally estimated (1,200 euro)?
A. Yes , at the moment we will keep the price, but I´ll confirm you when we will make the 2nd unit!

Q. How long will it take to put into production?
A. We can start the production in middle of September

Videos:
Karbonius carbon fibre S54 plenum
https://youtube.com/shorts/NtCRPz1705A?feature=share

Karbonius CSL-style intake
https://youtube.com/shorts/D8S_IVLXTEc?feature=share

OEM
https://youtube.com/shorts/LV8jRFmXMyg?feature=share

That's actually a really good video showing that the TB want more air than the OEM intake can provide..
Very interesting. I wouldent worry about the flex too much, KB make excellent products and they know the materials they work with, unlike some other rubbish companies.. yeah I am looking at you Evolve.

Very cool project, and lovely sound. Nice job so far Mban.

[MBan]

Thanks, Vanne!

Originally Posted by RvsBmw

Would you ask if they will make an elbow + airbox (front part) or if they are willing to think about? Don't want too buy an eventuri kit too (don't have one atm). They make that for the e9x v8 too:

Thanks for asking.

Karbonius said that they did think about making an elbow and airbox when they were testing plenum. Apparently this could 'maybe' be the next step but will be a few months before they could give it any attention.

[maupineda]

Originally Posted by MBan

Can anyone confirm if Z4 and post-2004 M3 rubber couplings work with the CSL airbox? I have never read that they DON'T, but would like to confirm as the rubber boots are quite expensive.

Yes, I have their CSL box and those pre-LCI E46 M3 boots fit our cars, the difference is on the box side, not the throttle bodies. We are good. (As long as you get the old style boots)

[MBan]

Karbonius have added a 'pillar' to the plenum to reduce the flex and re-tested. Volume appears to be unaffected. Possibly there's a slight change in tone? Video below.

To plan a production run, Karbonius are asking for people to indicate if they intend to buy one. I'll start a list in the next post. Don't forget that Z4 people and post-10/2004 M3s will need to buy the old rubber couplings and matching clips for the plenum side (parts 3 and 4 here https://www.realoem.com/bmw/enUS/sho...diagId=11_3517. Or, you can buy the Turner silicone coupling kit, which is quite a bit cheaper than buying new OE parts.

Karbonius plenum with extra reinforcing:
https://youtube.com/shorts/-6nf6_zrNxY?feature=share

Karbonius plenum without reinforcing:
https://youtube.com/shorts/NtCRPz1705A?feature=share

[MBan]

List of people committed to buying a plenum:
1. MBan
2. Barryb97
3. Polarbert
4. Kuky
5. maupineda
6. 86Zed
7. R717
8. survivalist
9. alfadog
10. 9kracing
11. JuicyM3
12. cliptheapex
13. gregl342
14. henderson_louie
15. theBMWaddict
16. Jdmaflac
17. Nicholas T (FB)
18. TeddybearCup
19. Kevin T (FB)
20. GuggagZ4M
21. jrgatfh
22. TurboDream17
23. Ddot12
24. LateBraking
25. hopz121
26. flipjohannon
27. PayamSFU
28. Mark A (FB)
29. Plunky
30. HBC (pending testing to make sure no power loss)
31. Mousitch

[maupineda]

I will buy

[MBan]

Originally Posted by maupineda

I will buy

Thanks - I've added you to the list.

[TurboDream17]

So $1200 for the intake itself, and another $350-400 in parts to make it work for the Z4 - does that sound accurate?

[Jdmaflac]

I’ll need to verify which year motor was swapped into my chassis but for the aftermarket couplers, we are referring to these correct? Great alternative to the OEMs for the price.

https://www.turnermotorsport.com/p-5...t-with-clamps/