"These build journal entries are part of a Special Series on the development of the S85 CSL Style Carbon Plenum and S85 CSL Competition Complete Carbon Intake System.

In this entry, I document the installation of the AlphaN IAT relocation kits and I service my cone filters after over 2 years of use." 
- Matt

AlphaN needs a new reading. 

The S85 CSL Competition Complete Carbon Intake System and the OE+ S85 CSL Style Carbon Plenum both require AlphaN software calibration to fully operate.

To operate under AlphaN protocols, the MSS65 requires an Air Intake Temperature (IAT) reading along with a Pressure reading to properly adjust fuel trims, ignition timing and other key variables of a properly functioning V10 M5/6. 

For a complete run down on how AlphaN protocols operate, read the entry "Alpha V10".

Due to air intake space maximization, the larger diameter Competition upper intake inlet do not incorporate bungs for the MAF sensors. 

The MAF sensors were previously used as IAT sensors for the OE+  S85 CSL Style Carbon Plenum and the standard S85 Sealed Carbon Intakes. 

As such, we need to install and relocate new Intake Air Temperature sensors. 

The kit includes new OEM quality Bosch sensors with threaded sections to easily install. 

Each sensor is wired to an OE style connector, that plugs into the original MAF sensor connector on the engine harness. 

This connector - you have two, one per bank. 

To install the IAT relocation kit, I highly recommend you remove the sealed intakes from the plenum to easily access the wheel liners from the engine bay. 

The connectors get plugged and zip tied. On the passenger side, I personally used this coolant line, some use the AC line

On the driver side, I used the electricals line covered in a plastic hose.. 

You'll need to remove the front wheels, and unbolt the front liner to access the lower bumper air ducts that leading to the intakes. 

I put the IAT sensor on the undertray to assess where I would drill to bolt the sensor for optimal readings. 

You'll need a drill and the appropriately sized drill bit. I don't remember the exact size as I'm writing this 7 months late (!). 

You can make out the properly ratchet wrench size though: 19mm. 

The IAT kit comes with a lock-tooth washer that bites into the plastic as you thread in the bolt on the sensor.  Proceed with this installation on both sides, doing your best to match the position. 

Serviceable, or replaceable filters. 

The original cone filters provided with the S85 Sealed Carbon Intakes and the complete CSL Competition Intake kit are oiled. Oiled filters are better suited for performance application, as was the original filter of the M3 CSL carbon airbox made by BMC. 

Ensuring these filters remain oiled is critical to its adequate filtration capabilities as they function as contaminant traps. The oil is the bait - less oil, less filtration. Oiled filters usually start at 1% less filtration abilities versus dry filter, but eventually degrade.  

OEM car manufacturers will have you believe they need to be changed or cleaned every 10,000 kilometers. K&N will tell you 50,000 kilometers for most filters, and up to 100,000 for larger conical filters. 

Installed in January 2022 at 125,000km, these filters had seen +/- 40,000 kilometers of all-weather use, including harsh Winter conditions of Quebec. 

The exposed sides were dirty, pebbles, sand and dust covered the filters.

Both filters showed signs of discolouration - an indicator of a lack of oil. 

The engine side of the filters were clean, showing little discolouration - this was a good sign. The filters were still fulfilling their tasks. 

I used K&N "Recharger" kit. It's commonly available in most auto parts store for +/- 20$. The kit includes a cleaning agent, and oil. 

The steps are straight forward: spray, rinse, dry, oil. Repeat step 1 and 2 if it's quite dirty. I did for good measure. 

Cleaner sprayed. 

Cleaner rinsed. No mechanical action is needed. I did manually remove some rocks and pebbles stuck in the plies. 

You want to spray contrary to what I have shown above: from the clean engine side towards the exposed, dirty side. 

The dirt was visibly removed, but the cleaner did nothing for discolouration. 

AH! That's what the oil is actually for. It's tinted red, allowing you to visually see where you are spraying the new oil. The difference is obvious.  

Oil should be sprayed everywhere inside and outside of the filter, ensuring it reaches between each plies. 

Give it 20 minutes to wick and dry. 

The oil pooling was present before I sprayed the oil. The original manufacturer generously applies it. 

With the filters cleaned and oiled, I begun reassembly of the intakes. I was able to fit the fully assembled intake on the passenger side.

The driver side required assembly in the car due to the engine coolant lines running from the expansion reservoir. 

First, I slid the intake's lower housing with the clamp pre-fitted into the lower bumper and chassis air ducts,

The filter was put in afterwards. 

Bam! 

You can source the Alpha IAT kits here. Should you opt to replace the filters instead of cleaning them, it's right here.