Karbonius Carbon Fibre Stock S54 Plenum

[R60BBA]

Hey guys and gals,

Just bringing to your attention that a Z4 Forum member recently approached Karbonius to see if they were interested in producing a carbon fibre airbox version of the stock S54 plenum.

In response, Karbonius mentioned that if they had interest of 20 or more orders they would consider developing one.

The main benefit of this proposition is that the induction noise would be closer to that of the CSL, but there would be no need of having to go down the Alpha-N or CSL map route - ie no need to remap the existing ECU.

Note, it is unlikely that there will be any power gains from this modification, and so the main purpose would be to enhance the induction noise.

At the moment there is no definite pricing but Karbonius have mentioned that it may cost circa €1,200.

If you are interested, post on here and I will relay this over to the chap on the Z4 Forum.

See more here: https://z4-forum.com/forum/viewtopic.php?t=134044 and here: https://www.zpost.com/forums/showthread.php?t=1900559

[Epoustouflant]

3,000 euros is the complete cost of a CSL airbox conversion including all the hardware & software, even for a pre facelift car.

Tough sell.

The OEM intake manifold is 2 pieces right?

If you're after sound only and a lower price point, it might be beneficial to look into a design that reuses your OEM plenum trumpets and strictly replaces the lid. It's a popular design on the E92 M3.

For reference, see below.

This sells for about 1,400$ without a core exchange service and comes fully assembled with the OEM lower section.

It sounds like this.

I can poke René for interest, and see what quantity / price point he'd see this at.

[Cronenberged]

3,000 euros is the complete cost of a CSL airbox conversion including all the hardware & software, even for a pre facelift car.

Tough sell.

The OEM intake manifold is 2 pieces right?

If you're after sound only and a lower price point, it might be beneficial to look into a design that reuses your OEM plenum trumpets and strictly replaces the lid. It's a popular design on the E92 M3.

For reference, see below.

This sells for about 1,400$ without a core exchange service and comes fully assembled with the OEM lower section.

It sounds like this.

I can poke René for interest, and see what quantity / price point he'd see this at.

If I remember correctly the stock intake design wouldn't be able to accommodate a top half or even a face front half. I agree at 3k you could have a CSL intake, hardware and tune to fix the mapping issues.

[Sprp85]

FYI, according to one of members in the other forum, the pricing got updated (Still a rough estimate) to 1,200 Euro.

[WoGGo]

3,000 euros is the complete cost of a CSL airbox conversion including all the hardware & software, even for a pre facelift car.

From the Zpost thread:

The 3,000 euro comment from Karbonius is the cost to them to make the mould.

and...

Karbonius has provided a rough price: 1,200 Euro.

[maupineda]

I would do it and I already have a Karb CSL airbox. MAF tune is just more effective.

[Epoustouflant]

FYI, according to one of members in the other forum, the pricing got updated (Still a rough estimate) to 1,200 Euro.

That makes much more sense.

[jet_dogg]

So bizarre to me why people are irrationally afraid of proper tuning.

Agreed, tough sell but good luck.

[Casa de Mesa]

So bizarre to me why people are irrationally afraid of proper tuning.

Agreed, tough sell but good luck.

Proper tuning is essential. Totally agree.

A few questions for the uninformed (me ):

If the airbox is essentially a clone of the stock intake plenum, how does that impact sound? Seems to me it might make a modicum more noise (more resonance due to thinner carbon), but has this been done? I also get how different materials might produce a different tone, but is volume a goal here too?

Here is my thinking. Perhaps a clone carbon box wouldn't have the same insulating properties as the stock one, but you wouldn't have the huge gaping hole sucking in air that you get with the CSL design. Sound is able to escape the CSL box pretty easily. With the clone, I can't imagine the induction noise would travel outside the confines of the stock air filter housing and associated plumbing any better than well... the stock plenum. It's bound to get trapped/muffled by the enclosures present with the factory airbox setup.

I'm asking from a point of curiosity, not trying to pee in the Cheerios...

[S54Mickey]

Count me in. Been on the fence for the past 2 years. Straight plug and play would be a win win for me.

[Sprp85]

If the airbox is essentially a clone of the stock intake plenum, how does that impact sound? Seems to me it might make a modicum more noise (more resonance due to thinner carbon), but has this been done? I also get how different materials might produce a different tone, but is volume a goal here too?

Indeed. The most ideal result from this would be the sound gain you get from S65 carbon plenum vs. stock plenum. There is a significant volume & tone change with the carbon plenum. And I believe the carbon plenum for S65 do maintain stock-ish internals.

[Cronenberged]

I'm asking from a point of curiosity, not trying to pee in the Cheerios...

😅😂🤣

[Epoustouflant]

Indeed. The most ideal result from this would be the sound gain you get from S65 carbon plenum vs. stock plenum. There is a significant volume & tone change with the carbon plenum. And I believe the carbon plenum for S65 do maintain stock-ish internals.

This is true!

Eventuri & CarboProject both retain the OEM trumpets design. The carbon allows for more resonance to pass through, and it is also thinner than the ABS used to make these plenums.

Karbonius & Haimus Racing both offer plenums with revised trumpet designs.

There would definitely be noticeable sound gains from an OEM intake manifold constructed from carbon fiber.

[zzyzx85]

fyi: this was posted in the Group Buy section a little while ago: https://nam3forum.com/forums/forum/m...s54-plenum-eoi

I think it's a great idea

[Nate047]

This won't be CARB legal either so what's the point