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

[TurboDream17]

Originally Posted by GuggagZ4M

But what is not well solved is the opening to the pipe bend/air duct. It slips off immediately because the opening is unfortunately conical. If you tighten the clamp, the pipe bend slips off and the wrong air is drawn in. In addition, the rubber seal that is present in the OEM box does not fit in between. So I first used two layers of adhesive tape and then tightened the pipe bend on top. This is not a nice solution, but it works for now. But be careful here too: even with adhesive tape, it can slip if you pull the clamp too tight.
By the way, I also tried this with the pipe bend of the M3 E46... was exactly the same result.

Sounds troublesome, and this is the production box, not a prototype, correct?

[GuggagZ4M]

Yes, this is the final production one. I wrote it already to Karbonius. Hope they will answer soon.

[Barryb97]

Back to the crankcase vent line. How did you extend it? Looks like a new one is $150 on ECS Tuning.

[MBan]

Originally Posted by GuggagZ4M

Hello all,

I received my box two days ago and installed it yesterday.

SOUND:
First of all about the sound "with" Eventuri kit: Yes, it really is 1:1 like an open airbox. Maybe 5% quieter. But the sound etc. is 1:1 identical (I recently drove a Z4M with an open airbox).

So it's really cool.

Comparison to Eventuri and sound generator:
At the same time, I drove the Eventuri one day before (to have a comparison that is close in time) and again with the Eventuri "and" my self-designed sound generator.

And I have to say: I still don't want to miss the airbox from Karbonius, because you also have beautiful carbon.
By the way, the box only weighs 1450 grams. The original OEM airbox weighs 4.2 kg... so that's a saving of about 2.8 kg.

But at the same time I also think....
For 1950€ (that's the cost of the Karbonius airbox incl. German 19% tax, shipping and the original BMW rubber nozzles) + 925Euro for the Eventuri Intake, you can also "actually" drive my sound generator just as well for only 400 Euros. Because the difference is almost non-existent. The sound generator is just as loud in the interior (without Eventuri!... with Eventuri it might even be minimally louder). It only produces a little more bass. Otherwise, the sound experience is almost identical... because the sound generator captures exactly the same sounds as the airbox produces. And also exactly the same rev ranges sound exactly the same (airbox as well as sound generator are only audible from approx. 3000 revs to approx. 5000 revs, after that the sound of both goes clearly back towards series, because the throttle valves close again and the VANOS switches differently).

So it's difficult, because it's actually super cool, but at the same time you think to yourself: for that money you can also buy the sound generator and then buy something else nice from the rest.

Nevertheless, I'm definitely keeping the Karbonius airbox for now.


And no, that's not meant as hidden marketing for my sound generator. Because the airbox is already cool... super well made, you have carbon etc.. But neutrally considered, it costs 4.5 times as much for an almost identical sound.


By the way, I wasn't able to generate any extra power. Yesterday it was 17.5 degrees and I was even about 0.4 seconds slower, although the tank was emptier than 2 weeks ago with just my sound generator.


Now to two shortcomings of the box:

In itself, the box fits well. But what is not well solved is the opening to the pipe bend/air duct. It slips off immediately because the opening is unfortunately conical. If you tighten the clamp, the pipe bend slips off and the wrong air is drawn in. In addition, the rubber seal that is present in the OEM box does not fit in between. So I first used two layers of adhesive tape and then tightened the pipe bend on top. This is not a nice solution, but it works for now. But be careful here too: even with adhesive tape, it can slip if you pull the clamp too tight.
By the way, I also tried this with the pipe bend of the M3 E46... was exactly the same result.

What's also a bit strange is that the oil dipstick now sits directly on the airbox. So there's almost no air, whereas with the OEM there was around 7-10 mm air.

Last thing: You also need a new crankcase breather hose. The original one is a bit too short. I cut mine in the middle and then lengthened it. An original one will therefore be ordered today, which would then fit again during reassembly.

All in all, it's still great.

Would I buy the box again? I don't know... At a price of 1300 euros including the BMW hoses etc., definitely! But at almost 2000 euros, I'm not sure.

Thanks for posting up your experience!

Definitely keen to hear what Karbonius say about your comments. With the crankcase breather hose, what hose are you ordering that is longer than the stock one?

[maupineda]

Originally Posted by Barryb97

Back to the crankcase vent line. How did you extend it? Looks like a new one is $150 on ECS Tuning.

Bear in mind you need this regardless of OE style, or CSL replica. that is not a fault of the OE-style box.

[maupineda]

Originally Posted by MBan

Thanks for posting up your experience!

Definitely keen to hear what Karbonius say about your comments. With the crankcase breather hose, what hose are you ordering that is longer than the stock one?

The CSL OE is longer.

[Barryb97]

P/n 11157833649?

[MBan]

Originally Posted by maupineda

The CSL OE is longer.

Thanks - I'll order the CSL part.

[GuggagZ4M]

I ordered as well the CSL hose (and a new one for z4m, if I want go back to stock Airbox).

EDIT: I will get the hoses today. Then I can tell you if the CSL version will fit or not.

[Kuky]

instead of getting a new CSL hose, what about using this opportunity to install an oil catch can?

[maupineda]

For those of you with US spec cars, the CSL breather hose misses the electronic check valve, you need to heat the hoses to separate them and make one out of the two. That is how is done in my Z4M

Or… Just get vacuum hose material and make your own.

[GuggagZ4M]

Originally Posted by Kuky

instead of getting a new CSL hose, what about using this opportunity to install an oil catch can?

Why would you don't use the csl hoses?

Think about That… that a little bit oildust in the Airbox is good for the engine because inlet side and its valve stems are lubricated with oil.

The orig. CSL hoses fits as well. I got my one 1 hour ago and test it directly.

It cost 33€ in germany inkl. Vat at bmw store.

[maupineda]

Super fast delivery. Bought Monday, received today. Super fast Spain to Mexico.

[Kuky]

Originally Posted by maupineda

For those of you with US spec cars, the CSL breather hose misses the electronic check valve, you need to heat the hoses to separate them and make one out of the two. That is how is done in my Z4M

Or… Just get vacuum hose material and make your own.

when you have a chance, can you upload pictures of your installation? thx

[maupineda]

Reserved for the unboxing photos 😬 …

The quality of the airbox is really OEM like, there could be a few interfaces where the two pieces meet each other that could be better, but it is impressive indeed.

[maupineda]

Originally Posted by Kuky

when you have a chance, can you upload pictures of your installation? thx

Here you go…



See the PCV hose, it uses the airbox half of the CSL OE hose mated to the original PCV solenoide (engine side)

To make this, you heat the hose to separate it from the quick connectors

[Polarbert]

I too didn't realise I'd need the csl breather hose. I'm in two minds whether to wait and check with my local bmw dealer for it, or order it from turner motorsport.

I was too excited and ended up duct taping my breather hose temporarily. The sounds excellent. It's just more of everything really.

Fingers crossed I can swap this all back over easily come smog time.

[TurboDream17]

Ordered mine today — will be running this + eventuri intake + the sound invention. I need as much sound as possible to hear anything with my RPi 😜 Hope it’s glorious!

[86Zed]

Any other comments on the airbox fitment to the ducting / intake air scoop?

[07ImolaRot]

Originally Posted by Polarbert

Fingers crossed I can swap this all back over easily come smog time.

I don't see how it affects smog. The air cleaner is still OEM. Technically one should pass with it, unless the tech picks on the fact that it is aftermarket.

[TurboDream17]

Originally Posted by 07ImolaRot

I don't see how it affects smog. The air cleaner is still OEM. Technically one should pass with it, unless the tech picks on the fact that it is aftermarket.

Unfortunately it’s not just a sniffer test (as it should be) - it includes a visual inspection under the hood, and anything aftermarket on the intake side that isn’t marked with a CARB sticker is a fail

Not to say it’s impossible to find a tech who doesn’t care, but in my experience most do.

[Westersund]

Originally Posted by GuggagZ4M

Why would you don't use the csl hoses?

Think about That… that a little bit oildust in the Airbox is good for the engine because inlet side and its valve stems are lubricated with oil.

The orig. CSL hoses fits as well. I got my one 1 hour ago and test it directly.

It cost 33€ in germany inkl. Vat at bmw store.

The point of rerouting the crankcase ventilation to the plenum is purely because of environmental reasons (laws). It's a good idea to install a catch can and from that route it back to the plenum to trap the oil mist in the can. If you don't route it back to the plenum it can get greasy around the filter if you have a badly designed catch can and it is ofcourse illegal on a street car. It has nothing to do with lubrication of the valve stems as the port injection cleans the valves anyway.