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

[3002 tii]

Originally Posted by 850tgul

Definitely notice a trend with folks going down the Karb OE plenum + Eventuri path hoping it will satisfy their desire for the CSL sound only to be disappointed. As someone who is on that path now (I currently have Eventuri + SG with an incoming Karb OE on the way) I hope I am an outlier and am happy with the final sound. I have been warned that my combo will not replicate the CSL sound perfectly and have tempered my expectations a bit.

I'm a little hamstrung in that being a MA resident facing annual inspections, I would have to reinstall the stock intake and flash back to stock every year to pass, which I am not ready to do, so fingers crossed the combo will be "good enough" for me.

Why wouldn’t a regular CSL box pass emissions?

[850tgul]

Originally Posted by 3002 tii

Why wouldn’t a regular CSL box pass emissions?

Per Josh @ Severn Tuning when I inquired about passing MA inspections:

"Emissions will be an issue. This is not specific to our tune. The Z4M requires MAF readings before it will commence onboard emissions testing. All alpha-n tunes will show “not ready” irrespective of the tuner. While I have gotten alpha-n cars through emissions in the past, it’s not something we offer any more due to the labor involved. I’d estimate it takes me 5-10x the number of revisions to get the parameters exactly correct for the monitors to set. Even then, a check engine light can be randomly and erroneously triggered due to the sensitivity of the ECU to the modified parameters. From a tuner’s perspective, it’s better to disable testing altogether, and it’s not fair to the customer to charge what we would need to make up for the labor involved."

[MBan]

I converted to full CSL style after running the OE style plenum plus eventuri for about a year. I reckon if you had a completely stock exhaust, this combo may be enough. However, I had superspint headers and s-pipe (at the time I also had SS powerloops) and the exhaust was competing with the intake. I also wasn’t super keen on the bitsa look with the plenum and eventuri - the full CSL looks much cleaner.

Using just the plenum with OE airbox and stock exhaust would be cool but it doesn’t fit as the plenum contacts the airbox. You could maybe modify the airbox but I wasn’t game.

[850tgul]

I need more time with the setup but after ~30 minutes of driving with the Karb OE box now installed along with an Eventuri and modified SG, I can't say I notice much more volume or a change in tone with the Karb OE box. It sounds very similar to my Eventuri + SG setup with the stock plenum. I do plan to take out my SG to test just the Eventuri + Karb OE setup to see if that gives a closer representation of the CSL bark that the SG somewhat sanitizes. Thing is, I know removing the SG will dramatically reduce the level of intake volume that comes into the cabin, so I'm not sure where I'll land in the end.

[maupineda]

The stock air filter box makes the sound attribute to be more present.

[BLKZ4MC]

Interested to see if we get more people will they be willing to work on price. Potentially interested based on final cost

[3002 tii]

Originally Posted by BLKZ4MC

Interested to see if we get more people will they be willing to work on price. Potentially interested based on final cost

This group buy was from 3 years ago.

[850tgul]

Originally Posted by 850tgul

I need more time with the setup but after ~30 minutes of driving with the Karb OE box now installed along with an Eventuri and modified SG, I can't say I notice much more volume or a change in tone with the Karb OE box. It sounds very similar to my Eventuri + SG setup with the stock plenum. I do plan to take out my SG to test just the Eventuri + Karb OE setup to see if that gives a closer representation of the CSL bark that the SG somewhat sanitizes. Thing is, I know removing the SG will dramatically reduce the level of intake volume that comes into the cabin, so I'm not sure where I'll land in the end.

Yesterday I disconnected my SG to see what the Karb OE + Eventuri combo would sound like and went for a drive. While removing the SG from the equation did eliminate some of that "hollow" sound the SG gives off (hard to describe but remember listening to things with a paper towel roll up to your ear when you were a kid, the SG kind of sounds like that because it is piping the induction noise into the cabin through a tube), I much prefer the Karb OE + Eventuri + SG combo and will be sticking with that for the time being. Even with the hollow sound from the SG, the overall intake noise and increased volume is much more intoxicating with the SG hooked up imo.