CSL MAP Sensor Solutions

[ATB88]

I now find myself with a CSL airbox, and I suspect many other forum members will in the next month as Turner keeps shipping. I remember that there was an informative thread on the old m3f discussing the various solutions out there for retrofitting the MAP sensor. Mods, is there any chance of bringing that thread back or is it lost?

There seem to be many choices out there, and I was hoping to become more educated about any pros/cons among them before I make a choice.

I'm aware of the following options right now:

-TTFS ($365 for a stock air rail that has been modified to have a MAP sensor mounting point, and a MAP sensor, after $350 core refund from sending them your original air rail: http://tuningtechfs.com/ttfs-e46-m3-...nd-map-sensor/)

-Kassel ($235, modified air rail tube with MAP sensor fitted to it. concerns have been raised in another thread here showing that the mounting location seems to add noise to the MAP signal, probably from vibrations coming through the throttle body which the idle air tube is mounted directly onto. no concrete evidence has been given that this causes any driveability problems whatsoever. https://www.kasselperformance.com/pr...onversion-kit/)

-Forum member COVID-19 offers his own retrofit kit, which mitigates the above possible issue with the Kassel setup by tapping the MAP sensor into the vacuum line between the brake booster and air rail ($110!!! see here https://nam3forum.com/forums/forum/c...conversion-kit)

-OE BMW CSL air rail ($385 and not shipping anytime soon from ECS: https://www.ecstuning.com/b-genuine-...417833597~geb/) and OE BMW MAP sensor ($349 at ECS, ships in sept: https://www.ecstuning.com/b-genuine-...528091765~oeb/). From what I understand, the issue here is that there was a recent transition in the actual part BMW supplies for the MAP sensor. The old one is perfect, but NLA and probably quite expensive if you can find it. From what I remember from discussions on M3F, the new one mounts quite poorly to the air rail and requires some modification to actually install properly? Is that right?

Questions:

1. Among these options, are the MAP sensors themselves being offered the same? And if yes, "actually" the same or just "functionally" the same? I see mention of things like "uses same scaling as BMW MAP sensor", and I also saw people dispute some of these claims back on M3F (can't remember details or outcomes of said disputes). Is this something I need to worry about? Do any of the non OE options offer an identical sensor to the OE sensor (new or old)? I remember hearing that one of the aftermarket solutions actually uses a GM sensor.

2. If someone wanted to shell out the big bucks and go the OE route, is the "new" OE MAP sensor a pain in the ass to get to mount properly or is it just a minor thing?

3. Is there any reason (other than vibration in the case of the Kassel kit) to think that having the MAP sensor installed anywhere other than the OE position on the air rail might cause slightly different behavior? (I suspect the answer is no, but open to hearing about people's beliefs on this one)

4. Any other solutions to be aware of? I remember the old thread on M3F mentioned a solution conceived by forum member NZ_M3 (or something like that) which seemed to be favored by people. What was the deal with that?

I'm going to keep on researching but would be very thankful for input from y'all!

[DiscoWagon]

Here's another one from Lang Racing, looks like it taps the vacuum line by the brake booster as well. Available just as an adapter or with your choice of sensor. Haven't actually seen anyone running this one though.

https://store.langracing.com/s54-map...fi-conversion/

[repoman89]

Use this if you go with the OE CSL air rail. This MAP sensor is the same one Kassel uses in his kit I believe.

http://www.cslregister.com/forum/showthread.php?t=14786

[ATB88]

Use this if you go with the OE CSL air rail. This MAP sensor is the same one Kassel uses in his kit I believe.

http://www.cslregister.com/forum/showthread.php?t=14786

Ah yes, that's the NZ_M3 solution. Thanks!!

Informative read that answers some of my questions -- from what I understand, the sensor that Kassel and COVID-19 are using is electronically identical to the old OE sensor (and new one), just packaged differently. Also, indeed, the new OE BMW sensor seems to be garbage in terms of fit.

If one wanted the "OE look" with the OE CSL air rail, one could use that sensor (which is cheaply and readily available), but it sounds like you need: 1) to find a way to space the sensor 1.5mm up to compensate for the longer nose without creating a vacuum leak, and 2) get the same diameter o-ring used on the BMW sensor. I'm very tempted to go with this option. But, while I'm sure those 2 challenges are pretty easy to overcome for anyone who has experience with this kind of stuff, I'm not very handy. Has anyone gone this route and has an easy "just buy this and do this" way of getting this to work? If not, the COVID-19 route seems like a no-brainer for me.

[rbg]

In order for this sensor to fit the CSL air rail, all that was needed was 0.5mm shaved off the nose inlet on the sensor with a craft knife (very easy to do) and then I purchased a Viton O-Ring size 8mm ID x 3mm cross section thickness (the original seal that came with the sensor is 8mm ID x 2.5mm cross section which was a little loose for my liking). It was a perfect fit. Everything bolted up like it was made for it.

Sounds like a pretty simple solution to me, no?

[ATB88]

Sounds like a pretty simple solution to me, no?

Whoops, missed that part of the second post. Perfect!

[rbg]

Thats the option I went. I actually picked up that last rail from ECS. Was sell out sale or smth.

[ATB88]

Thats the option I went. I actually picked up that last rail from ECS. Was sell out sale or smth.

Nice, I was thinking last month whether I should grab it before they sell out and now annoyed with myself that I didn't

I'll see if Schmiedmann has access to them right now, if not I'll just do the COVID-19 route and then consider upgrading to the ~*OE*~ setup later on if I feel like it.

One other question: IAT sensors. I see most people using this one: https://www.turnermotorsport.com/p-1...uine-bmw-part/

but the part number on realoem for the CSL is actually this one: https://www.ecstuning.com/b-genuine-...r/13621739510/

I assume that they're functionally identical? Any good reason to use one over the other?

[rbg]

I have the first one, I honestly don't know why :-)

[COVID-19]

IAT sensors 1 & 2 use different scaling. You can modify it with Ecuworx but when tuning tell your tuner which sensor you are using. I believe CSL software comes for IAT 2.

[heinzboehmer]

Nice, I was thinking last month whether I should grab it before they sell out and now annoyed with myself that I didn't

I'll see if Schmiedmann has access to them right now, if not I'll just do the COVID-19 route and then consider upgrading to the ~*OE*~ setup later on if I feel like it.

One other question: IAT sensors. I see most people using this one: https://www.turnermotorsport.com/p-1...uine-bmw-part/

but the part number on realoem for the CSL is actually this one: https://www.ecstuning.com/b-genuine-...r/13621739510/

I assume that they're functionally identical? Any good reason to use one over the other?

VNE is OE for the CSL sensor. Significantly cheaper: https://www.fcpeuro.com/products/bmw...739510#reviews

[ATB88]

IAT sensors 1 & 2 use different scaling. You can modify it with Ecuworx but when tuning tell your tuner which sensor you are using. I believe CSL software comes for IAT 2.

Excellent! Glad I asked.

[Cubieman]

IAT Option 2 = CSL Scaling
IAT Option 1= US Spec.

[ATB88]

IAT Option 2 = CSL Scaling
IAT Option 1= US Spec.

Option 2 also seems like it would be better to use from the standpoint of heatsoak -- it has the actual sensor element exposed to the airflow inside the box which would keep it cooler, rather than being covered in plastic which will hold on to heat and therefore heatsoak. This seems like it should be an important consideration given that the IAT sensor on the CSL box is right by the oil filter housing and radiator. I guess sensor 1's probably fine if you relocated it to the snorkel or something? In any case I don't see any reason not to use sensor 2 in any CSL airbox situation.

[terra]

Ah yes, that's the NZ_M3 solution. Thanks!!

Informative read that answers some of my questions -- from what I understand, the sensor that Kassel and COVID-19 are using is electronically identical to the old OE sensor (and new one), just packaged differently. Also, indeed, the new OE BMW sensor seems to be garbage in terms of fit.

If one wanted the "OE look" with the OE CSL air rail, one could use that sensor (which is cheaply and readily available), but it sounds like you need: 1) to find a way to space the sensor 1.5mm up to compensate for the longer nose without creating a vacuum leak, and 2) get the same diameter o-ring used on the BMW sensor. I'm very tempted to go with this option. But, while I'm sure those 2 challenges are pretty easy to overcome for anyone who has experience with this kind of stuff, I'm not very handy. Has anyone gone this route and has an easy "just buy this and do this" way of getting this to work? If not, the COVID-19 route seems like a no-brainer for me.

for the spacing, I’d just shave 1.5+ mm off the sensor nose. You don’t need to be precise.