Karbonius

[Slideways]

I have an issue at idle speed, just letting off clutch (no gas pedal input) and moving down the driveway the RPM's will surge and the vehicle "bucks" or "jerks" as the RPM's rapidly move up/down.

I am running the flap and have my IAT located down at the very bottom of the snorkel near the brake duct area. I wonder if maybe the DME is getting confused by pulling cold temps from my IAT location but the flap is closed at idle thus the airbox is pulling it's air from smaller rear hole which is pulling nothing but extremely hot engine bay air.

Might be something to that, I used to have ducting from the rear hole to the brake duct so it would pull colder air but have since done away with it, I want to say the same issue occurred then as well.

Might just be a dirty ICV which I forgot to clean during airbox install or possibly TPS(s).

This seems to be normal for the MAP setup. The RPMs will surge two or three times before the clutch is fully engaged. Remedy is to add more throttle or slip the clutch longer. With very little throttle, it's not as easy to slowly pull away from a stop as it is on a MAF setup.

[jbfrancis3]

This seems to be normal for the MAP setup. The RPMs will surge two or three times before the clutch is fully engaged. Remedy is to add more throttle or slip the clutch longer. With very little throttle, it's not as easy to slowly pull away from a stop as it is on a MAF setup.

I do not find that to be normal when using my vehicle as a baseline. I have the same setup as Cubie (including IAT location) and it behaves like stock at idle and off the line. It did not used to be perfect (not as bad as Cubie's description) but after PCS Tuning it is actually perfect.

[Slideways]

I do not find that to be normal when using my vehicle as a baseline. I have the same setup as Cubie (including IAT location) and it behaves like stock at idle and off the line. It did not used to be perfect (not as bad as Cubie's description) but after PCS Tuning it is actually perfect.

Three different MAP setups tested had the same response off idle. Here is a video of M3Dragons CSL clone and you can see and hear it at 0:22:

[jbfrancis3]

Three different MAP setups tested had the same response off idle. Here is a video of M3Dragons CSL clone and you can see and hear it at 0:22:

I don’t have that. I was willing to accept compromises such as that when first making the modifications but was pleased to end up with excellent low speed/low RPM behaviors. Credit needs to be given when credit is due which I mentioned prior.

[Cubieman]

I don’t have that. I was willing to accept compromises such as that when first making the modifications but was pleased to end up with excellent low speed/low RPM behaviors. Credit needs to be given when credit is due which I mentioned prior.

Did you get a dyno tune and/or use AFR/datalog or simply a canned tune? I need to use BMWlogger and send some data to Hassan to see if this can be resolved.
Part of me wants to throw parts at it (TPS) as I will have the airbox off soon and would gain access the harder of the TPS's. I would like to at least test the TPS's with a multimeter if the values are known.

[repoman89]

I don’t have that. I was willing to accept compromises such as that when first making the modifications but was pleased to end up with excellent low speed/low RPM behaviors. Credit needs to be given when credit is due which I mentioned prior.

I don’t have it either, same tuner.

[jbfrancis3]

Did you get a dyno tune and/or use AFR/datalog or simply a canned tune? I need to use BMWlogger and send some data to Hassan to see if this can be reminded.
Part of me wants to throw parts at it (TPS) as I will have the airbox off soon and would gain access the harder of the TPS's. I would like to at least test the TPS's with a multimeter if the values are known.

Eventually, dyno tune with AFRs logged on the runs. But really, the sessions benefitted the power pulls. I began with the tuner's 'base' tune which still reflects a lot development and years of tweaking. For the tuners here, it wouldn't be fair to call it a canned tune.

My view is this all falls under the category of some challenges (but addressable) that creep up when moving over to a CSL type airbox. I truly don't believe replacing a TPS or related parts will do anything, but as you know I'm at the opposite end of being an expert. Point I am trying to make is I have experienced variability across different tuners and then within those tunes, variability when a tuner changes a parameter or two, and well within the symptoms you experience. My journey was Kassel > FSTuning > PCS.

[Slideways]

I don’t have that. I was willing to accept compromises such as that when first making the modifications but was pleased to end up with excellent low speed/low RPM behaviors. Credit needs to be given when credit is due which I mentioned prior.

Two of the cars were using a PCS tune, but it happened even with the stock CSL tune. With the MAF, they responded normally with a one up and down of the rev needle. The CSL has this two up and down as the clutch is engaged and it picks up after the second RPM surge. It is most evident when moving the car in first or reverse with little to no throttle (starts after cold start sequence has ended where the RPMs stabilize at 950).

[Cubieman]

It is most evident when moving the car in first or reverse with little to no throttle (starts after cold start sequence has ended where the RPMs stabilize at 950).

Exactly.

[jet_dogg]

Speaking of which,

[Casa de Mesa]

Obioban or anyone else who happens to be running the Race version with the built in snorkel. All weekend, I've been hovering over the buy button on the Karbonius site for both an airbox and a trunk (for the $500 in shipping of that trunk per this thread, I figure might as well get an airbox shipped).

MY QUESTIONS:
1. Are you running any sort of ducting to the box to direct cold air? Ian, you said you were just running ducting from the kidney grills earlier in this thread. Is it just the factory duct work or something more complicated / custom?

Reason I ask - it *seems* like with the "regular" Karbonius CSL carbon box that you could get cooler air to that box more easily, given the provisions that exist via ideas in this thread and others. With the Race version, the opening at the bottom of that snorkel is quite wide, so getting cooler air to it seems (again... seems) like it might be more challenging. If I went with the regular Karb CSL box, I'd use their carbon snorkel.
2. Is anyone running their heat insulation kit? Don't love the look of it, but seems like a really great way to mitigate some of the heat soak issues mentioned in this thread, in particular post #49 by Anri.

Sorry for all the hyperlinked content. Hoping they help others in the future researching this...

-Casa

[Phoenix///M3]

That insulation kit is offensive to the beauty of the cf weave

Sent from my SM-G950U using Tapatalk

[Casa de Mesa]

That insulation kit is offensive to the beauty of the cf weave

Sent from my SM-G950U using Tapatalk

Can't say I disagree, was hoping someone had a pic of it to see how hidden it is or is not.

[SQ13]

Will there be no more Karbonius CSL intake group buys? I would like to buy two, but I’ll be in less pain if I can get them at a discounted price.

[sleeks]

Will there be no more Karbonius CSL intake group buys? I would like to buy two, but I’ll be in less pain if I can get them at a discounted price.

Probably not on the airbox. It’s their biggest seller. They don’t need to discount it.


Sent from my iPhone using Tapatalk