Karter16's Silbergrau E46 M3 Journal

[0-60motorsports]

Awesome work. Look into doing an SMG relocation. Parts are easily available.

[karter16]

Yesterday morning I completed the install of the airbox.

First up I took the wiring loom and laid it out in the engine bay to work out the best way to route everything (note the red ties temporarily holding it in place).



Once I'd done that I then temporarily installed the TB half of the airbox to get the position and orientation of the IAT sensor just right. I made sure to mark on the loom the orientation of the loom to the connector so that it sat just right. Then I uninstalled the airbox, removed the loom and attached the connectors for the MAP sensor and IAT.



The finished loom


I then installed the loom for real, cable tying at appropriate points:


And here's how the MAF connector end looks:



With that done the only wiring left to do was to relocate Pin 1 of the X6003 connector to Pin 18 which was a quick job:



Then it was back in with the first half of the airbox for reals this time. All of the hoses and connectors fitted perfectly - I didn't run into any of the issues heinzboehmer did - maybe Karbonius have refined since? The only annoying thing was installing the 10mm nut for the rear vibration isolator - there's not much room to get in there.

I clamped up the throttle body boots and moved on to installing the MAP sensor. I'm super happy with how the MAP sensor adapter has turned out - it's worked out exactly how I envisioned it would (I've got more to say about this which I'll do as a separate post).




Filter in place:



Various top-side connections done:



Then it was a quick job to install the front half of the airbox and the snorkel:



And finally with the rest of the engine bay back together (you'll have to excuse the dirty car - I'm in the middle of significant landscaping and renovations at the moment at home and it simply isn't worth me spending much time cleaning anything up as the clay dust gets everywhere:




Then in the evening I flashed the Terra 0401 program binary to the car (after taking read backups of the current prog and tune) and then the partial binary with what I'm calling the "base modifications" to make the 0401 work with non-CSL cams, code out the DTC for the flap, etc.

This morning I started the car briefly to confirm it would start and there were no major issues. A bit later today Dad is coming round to (a) come along for the first test drive and (b) hold the data-logging laptop while I drive. The plan is to take it for a run on the "base modifications" binary, log and make sure things are working as they should be and for me to get a feel for what the base CSL tune is like (my exceptions are for it to be rubbish like everyone says). Then I'll flash V1 of my tune and do the same thing and cross my fingers that it's an improvement.

We'll find out :-)

[heinzboehmer]

Then it was back in with the first half of the airbox for reals this time. All of the hoses and connectors fitted perfectly - I didn't run into any of the issues heinzboehmer did - maybe Karbonius have refined since?

Nice, good to hear that newer airboxes don't have the same issues. Slideways and I bought airboxes from Karb around the same time and we've both had those issues with the hoses. However, don't think I've heard similar complaints from the other Bay Area friends with newer airboxes.

That reminds me, I still need to grind down the port for the small hose on the bottom...

[Bry5on]

The oil drain back to the pan has longer clip ‘fingers’ now than the original parts did. Not sure if this was a part number change, tolerance change or what. I didn’t replace the oil drain line originally and mine never stayed clipped in to the karb fitting for more than a couple drives. Bought a new line and it fits/clips like a glove.

On the other hand, almost all my fittings have come unglued one at a time from the airbox. Since mine is a daily, maybe it just sees more fatigue? 30k miles on the airbox now. Hope your epoxy stays set!

[Slideways]

Nice, good to hear that newer airboxes don't have the same issues. Slideways and I bought airboxes from Karb around the same time and we've both had those issues with the hoses. However, don't think I've heard similar complaints from the other Bay Area friends with newer airboxes.

That reminds me, I still need to grind down the port for the small hose on the bottom...

Needed a newer oil pan vent hose. Air shut off valve was a perfect fit though.

The snorkel needs a bit of choppy choppy action to get the full sound effect

[heinzboehmer]

The oil drain back to the pan has longer clip ‘fingers’ now than the original parts did. Not sure if this was a part number change, tolerance change or what. I didn’t replace the oil drain line originally and mine never stayed clipped in to the karb fitting for more than a couple drives. Bought a new line and it fits/clips like a glove.
On the other hand, almost all my fittings have come unglued one at a time from the airbox. Since mine is a daily, maybe it just sees more fatigue? 30k miles on the airbox now. Hope your epoxy stays set!

Needed a newer oil pan vent hose. Air shut off valve was a perfect fit though.

The snorkel needs a bit of choppy choppy action to get the full sound effect

Interesting. Neither of those hoses fit well on mine, even with the newer vent hose. New style hose is super close and hasn't fallen out yet, but it doesn't exactly clip into place.

Fortunately none of my fittings have come undone and my filter does seal well

[karter16]

The snorkel needs a bit of choppy choppy action to get the full sound effect

Yeah I'm planning on doing this based on your recommendation - I left as is for starters as wasn't sure how much additional noise I was in for at neighborhood speed/throttle and didn't want it to end up too loud, but having heard in person that it's fine in those conditions I'll now cut out the divider to get the full volume as you suggest!

[Bry5on]

The divider is functional (assuming you duct to the front bumper)! Just saying

[Slideways]

Yeah I'm planning on doing this based on your recommendation - I left as is for starters as wasn't sure how much additional noise I was in for at neighborhood speed/throttle and didn't want it to end up too loud, but having heard in person that it's fine in those conditions I'll now cut out the divider to get the full volume as you suggest!

If you want to test volume, try it without the snorkel. Sound is managed by throttle input.

[karter16]

Well the initial couple of drives have been very successful. Couple of one time codes on first start up related to TPS and 1 misfire code, which I think was the engine being mad at the change of program plus blowing out the carbon from the throttle body cleaning. No repeats of any codes in the two 20 minute drives I've done since.

First impressions: the base CSL tune was not as bad as I was expecting. The warm up was rubbish as expected and lots of idle hunting, etc. going on. Once the SAP turned off things settled down. Driving around at slow speed was much smoother than I was expecting. The up and go was a bit muted, but tip in with the SMG was exactly the same as before and there wasn't any jerkiness under light/moderate acceleration. I presume that the reason for this is that my car is a Euro car, which differs less from the CSL than a US spec car does. I know that the US and Euro tune vanos maps differ significantly in places, so that would explain why the standard tune is worse on a US spec car. The car was quite reasonable to drive in the various conditions I tested it in.

Given this I wasn't entirely sure how much of a difference I would notice with v1 of my tune (which I must point out again is simply me making my own version of the approach which Bry5on has pioneered). I loaded it up and the improvement was immediately noticeable. The CSL tune wasn't rough driving around the neighborhood and it wasn't enormously noticeable that it lacks in peppiness under those conditions, but when you bring the peppiness of the standard M3 tune back at those low load, low speed conditions it is immediately noticeable as an improvement. I've logged the run in TestO and will go through it later. I need to adjust a couple of the timing maps in the 3300-3900 rpm range (I haven't quite got the crossover lined up right with the VANOS maps crossover and need to adjust slightly, but it's not off by much).

Extremely happy with how this has all gone. No installation issues, no programming issues and a good success with v1 of the tune!

[karter16]

The divider is functional (assuming you duct to the front bumper)! Just saying

Hmmm this is a very good point - I shall ponder these implications some more.

If you want to test volume, try it without the snorkel. Sound is managed by throttle input.

Great point - thanks I'll do this first to get a feel for the difference in volume that we're talking about while I think more about Bry5on's comment

[Bry5on]

Hell yeah! Glad it's working out well. Listen for any pinging or bogging around 1800-2100 starting at roughly 2/3 throttle opening once you get a bit more seat time in it.

Do you have a Wideband O2 sensor? I still haven't gotten cold starts totally dialed in factory non-CSL perfect. I'm curious to see if you end up chasing the same thing I'm chasing. Congrats though!

[karter16]

Hell yeah! Glad it's working out well. Listen for any pinging or bogging around 1800-2100 starting at roughly 2/3 throttle opening once you get a bit more seat time in it.

Do you have a Wideband O2 sensor? I still haven't gotten cold starts totally dialed in factory non-CSL perfect. I'm curious to see if you end up chasing the same thing I'm chasing. Congrats though!

I'm really very grateful to you for coming up with this approach. I remember thinking a couple of years ago how nice it would be to have a "standard" tune or set of tunes for cars running a CSL airbox without the cams, etc. but I doubt I would have ever thought of achieving that in this way, you having come up with this approach and proving it out is what gave me the encouragement to give it a go!

Yeah I just need more seat time in it now I think. I loaded "v2" this afternoon which has fixed the murkiness through the 3300-4000 rpm range, now seems super smooth in a bunch of different load/throttle conditions. I don't have a Wideband sensor yet but intend to get one to help with the next layer of fine tuning, WOT tuning, etc.

For v2 (having proven that v1 wasn't a dud) I added in the various cold start/warm up maps (I had to dive into the disassembly to validate a couple of things as some of the table values are very different between the 0401 binary and the 1901 binary that my car started with) and from an almost completely cold start (coolant temp a few degrees above ambient on what is admittedly a summer day here) the warm up seemed as it was on the standard M3 tune. I'll give it another go in the morning when it's cooler and the car is completely cold, but it seems a lot better than before.

[Bry5on]

I’m enjoying watching your approach as well and resisting the temptation of sending you the files to compare. I don’t want to interrupt your process and would really like to see if we converge on the same answers, particularly since I’ve been doing some maps with the wideband O2 sensor in the loop.

Most of my imperfect running is the first 60 seconds from full cold starts in ambient temps below 60F/16C. Lots of variables to chase in the cold start tuning, and to tune via AFR you’ve got to disable secondary air, etc etc. Plus you only get 60 seconds per day to tune while you’re taking meetings for your day job.. Fun.

As you get some seat time, I expect you’ll find idiosyncrasies to chase - looking forward to you getting more time in it, and happy to share notes if you find some odd stumps here and there. It was helpful for me to have a few friends cars here (thanks Heinz) to load tunes on to hone in on what worked best, as each car responded slightly differently to some changes, but all run well on a single converged file.