Karbonius

[Mattn1192]

I started with ITG and now run OEM filter and haven't noticed a difference.

What made you change?

[Cubieman]

What made you change?

I thought the ITG filter was letting debris into the filtered section due to fitment issues but instead my airbox itself had the fitment issue and was of debris behind the air filter which Karbonious has since corrected in future production runs and will fix mine if I send it back to them.

[jet_dogg]

Good to hear re: the change looking forward to it.

[terra]

I thought the ITG filter was letting debris into the filtered section due to fitment issues but instead my airbox itself had the fitment issue and was of debris behind the air filter which Karbonious has since corrected in future production runs and will fix mine if I send it back to them.

Huh, I guess I always just assumed they wouldn't bother. I've been using foam molding to fill up the space, but if Karbonius is willing to fix / exchange the airbox, that'd probably be worth it.

[terra]

That's why I'm not running the ducts.

It's in the OE location on the clean side of the filter. Not the best picture, but the first one I found in my library where you can see it:

Is there something fancy about the material the real CSL box uses there? My IAT on my karbonius reads significantly above ambient. Like 40+ higher.

[Cubieman]

Huh, I guess I always just assumed they wouldn't bother. I've been using foam molding to fill up the space, but if Karbonius is willing to fix / exchange the airbox, that'd probably be worth it.

Yea part of my ITG filter is in the gap. I will likely send my box over to them this winter though. They sent me this picture of the "repair".

[Obioban]

Is there something fancy about the material the real CSL box uses there? My IAT on my karbonius reads significantly above ambient. Like 40+ higher.

Nothing obviously fancy, from looking at it. But, it's ~ambient when I'm in motion, in that location.

[jbfrancis3]

Nothing obviously fancy, from looking at it. But, it's ~ambient when I'm in motion, in that location.

Is the sensor bung made of plastic or aluminum in the genuine CSL piece? The Karb box uses aluminum.

[Obioban]

Is the sensor bung made of plastic or aluminum in the genuine CSL piece? The Karb box uses aluminum.

Just went out to look. It's kind of hard to tell without scratching it (not willing to do that), but I believe it's plastic.

... mine is also not "genuine CSL"-- it was made by the company that made them for BMW, and, in the case of mine, before the CSL came out.

[paulclaude]

Under certain conditions, you will find that the stock CSL IAT location tends to see higher temps than when located elsewhere, I assume this is due to the close proximity to the oil filter housing. However, as long as you have adequate cold air ducting to the mouth of the airbox (commonly from bumper duct), temps should come down to within a few degC of ambient when the car is moving on the road. On my own dyno, I tend to add some extra ducting to the mouth of the airbox to direct some additional air and keep IAT stable for tuning - my main cooling fan doesn't direct airflow too well to the side bumper openings.

[Anri]

I assume this is due to the close proximity to the oil filter housing.

Paul,

The heat to the IAT is coming mainly from the 11blade 420mm fan clutch when it
engages. Depending on the temp in the dyno room the fan clutch comes on and off
on and off.

The BMW fan clutch rotates Clockwise when you sit in front of the car.That
said it pushes all of that hot air which is sucked from the radiator directly to
that exact area, filter housing, IAT sensor, and the front part of the box were the
IAT is mounted. Ones the hood is closed things are getting for the worst because
that hot air gets stuck under the hood.

Behr fan clutch engages at around ~90C and it shuts down at around ~60-75C
even when it shuts down the "free-rotation" is still directing hot air to the box then
the fan clutch cycles.

At 79/80C T stat on S54 and with the Vanos map for Cold start the engine temp
is very quickly up so that emissions are met and under the hood a lot of heat is stored.
My cup of tea is to delete this option not my cup of tea to so see the temp of the engine
to raise that fast.

I like to mount the sensor closer to the head light so its away from the fan clutch
heat.

On the S54 cooling system the Hot water exit from the Intake side right under the ITBs.
All of that heat quickly goes up in the ITBs and transfers that heat to the box, yes the
rubber boots don't transfer much heat but still does heat up the box.

Vents on the hood for sure helps to reduce engine bay temps.

Regards,
Anri

[paulclaude]

Paul,

The heat to the IAT is coming mainly from the 11blade 420mm fan clutch when it
engages. Depending on the temp in the dyno room the fan clutch comes on and off
on and off.

The BMW fan cutch rotates Clockwise when you sit in front of the car.That
said it pushes all of that hot air which is sucked from the radiator directly to
that exact area, filter housing, IAT sensor, and the front part of the box were the
IAT is mounted. Ones the hood is closed things are getting for the worst because
that hot air gets stuck under the hood.

Behr fan clutch engages at around ~90C and it shuts down at around ~60-75C
even when it shuts down the "free-rotation" is still directing hot air to the box then
the fan clutch cycles.

At 79/80C T stat on S54 and with the Vanos map for Cold start the engine temp
is very quickly up so that emissions are met and under the hood a lot of heat is stored.
My cup of tea is to delete this option not my cup of tea to so see the temp of the engine
to raise that fast.

I like to mount the sensor closer to the head light so its away from the fan clutch
heat.

On the S54 cooling system the Hot water exist from the Intake side right under the ITBs.
All of that heat quickly goes up in the ITBs and transfers that heat to the box, yes the
rubber boots don't transfer much heat but still does heat up the box.

Vents on the hood for sure helps to reduce engine bay temps.

Regards,
Anri

Anri,

Good point - hot airflow from the radiator clutch or other fan will certainly be an influencing factor. I agree that the IAT mounting towards the headlight negates the problem, although isn't exactly ideal as really you want the ECU to see the actual air temp in closest proximity to the throttle body openings as possible. However, although this is definitely an issue while stationary or in a dyno room, I don't think the location is much of a problem when the car is moving on the road as long as long you have a solid cold air feed to the mouth of the airbox. With the cold feed, IAT reading always seems to come down to within a few C of ambient from my own testing as previously mentioned.

Paul

[Anri]

I don't think the location is much of a problem when the car is moving on the road as long as long you have a solid cold air feed to the mouth of the airbox. With the cold feed, IAT reading always seems to come down to within a few C of ambient from my own testing as previously mentioned.Paul

Hi Paul,

Ideal always cost money and them often don't get it...

A CSL box or even std box to example. Nice custom snorkel which will be
insulated to suck air via pipe from outside the engine bay sort of "ram air" is
the way to go. The pipe must be absolute sealed so it does not leak air or
allow engine bay air to be blended...as the speed goes up say 40km/h+
the air is already being forced. The best place to have the IAT mounted
is in the custom pipe which will be located outside of the engine bay.
The IAT will get soaked by outside actual temp and its a win win.

During tune a small and very powerful fan should simulated
the road speed as good as it can get. Big fan should be used for the radiator
to maintain coolant temps in acceptable value. I have tested on the Dyno
if I direct a small fan on the intake the oxygen content goes up because
the air is now being forced and boom 6-7rwhp gain with minor touch on
the map table.

We know the coolant temperature is far more important than the few
degrees being improved on the IAT. One area I never liked on S54
is that the hot water exit is on the Intake side...that is very bad because
you are heating up the Intake path and who needs the 95C+ when driven
with anger heat to come outside from intake side ?...(I have a fix for that but
way to long to explain)

The BMW Engineering behind this has single benefit in the slant engine as ours
are. If there is any Air in the system by say leaky hose or any error in the cooling the air
will escape much easier away from the cylinder head and air will not get stuck in the system.
I would never ever trade this maintenance versus hot water going thru the intake side...

On S54 when the water enters the block it goes around the cylinders and being
forced to take the heat from the Exhaust Valves and pushes the water via the intake
side. The cylinder head gasket has restrictors so that the water flows from the exhaust
side and being forced to go across the cylinder head and will exit on the intake side.

On L6 Bank-2 always runs hotter and the EGT will always show higher on 5-6cyl.
A trick I always do is when temps go up on 5-6cyl I reduce the timing by say 0.5-1 degree
and add very little more fuel so that they will balanced the heat.

Sorry for the long reply but there is so much to say and consider when one start
asking for proper performance..

Regards,
Anri

[Cubieman]

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).

[jet_dogg]

You're overthinking this.

I'd start with replacing both tps, sounds like your throttle input is not getting output correctly.