Karter16

Pretty sure I've finally found a source for the male MAF sensor connector that allows for MOQ of 1 (and it's cheap to boot). This is what I'm talking about: I've ordered a couple to check and confirm, but if it is then this is the missing piece for people to be able to build their own harness extensions (and IAT relocation extensions I guess, not that I think they're good idea) without having to pay Turner mark-up. It also means anyone wanting to do what I did (keep the MAF connector and wire up for MAP sensor) doesn't have to buy a Turner extension just to then hack it up to add on the Bosch MAP sensor connector, etc. I'll wait til these arrive and I've confirmed and then put up a post with all the various part numbers needed to do this.

Whole family (including myself) are sick this weekend so took the opportunity to try out doing a VE table tuning run with the MAP sensor turned off. I've been wanting to do this for a while as theoretically it's another variable that can be removed from the process. With the MAP sensor taken out of the RF calculation path the car is essentially running in "Alpha-N Mode". My theory behind this is that depending on point in time conditions the MAP sensor is adjusting the final RF either up or down from what's calculated from the VE table. While this is desirable in day to day use, for the VE tuning process it's an unwelcome additional variable. Unfortunately I can't really think of an objective way to measure the impact of it to the VE tuning process, so it's really just a subjective assessment I guess. The difference with the MAP sensor disabled is immediately noticeable in the part-throttle conditions the MAP sensor targets. The car is less responsive and throttle input is jerkier and less consistent. I found a couple of RO/RPM conditions which I hadn't previously been able to flush out. I intend to do another tuning run tomorrow or Monday on a day when I can get further out and up the RPM range more to get a more complete test. It would need more people to try this out and get their subjective feedback as well as to whether disabling the MAP sensor positively influences the VE tuning process (I think it will mostly be about the speed at which one arrives at the end result), but I am pleased to have finally proven out that changing the configuration byte from 0x12 to 0x02 does behave as expected. Oh and also gave the nylon MAP sensor adapter a couple of good heat cycles and then took it off and inspected it - appears to be unaffected by the heat so far, so off to a good start.

The MAP sensor adapter printed in CF-reinforced Nylon arrived today. Minimum order value applied so I'm now the proud owner of 12 of these. I'll try to install in the next couple of days. HDT is significantly higher than the CF-PETG I used previously.

Well yesterday and today I tackled a job I've long been putting off. Yesterday I took the headlining out of the car, and dropped it (along with the sunroof cover, etc) plus the BM-134 fabric off to a professional headliner upholsterer. The dude was a legend and had it ready for me to pick up this morning (think he was grateful that I'd done the hard work of taking it out of the car!). He was very complementary of the BM-134 fabric - he said it's a quality fabric with quality foam and was lovely to work with. I'll tackle pretty much any job on the car, but this is one of those few things I'm very happy to leave to a professional - the work is flawless and it looks incredible. For those wondering about the fabric match - I took some photos of the re-wrapped headliner against one of the interior trim pieces which has the original BMW fabric on it (non-foam-backed): It's a very close match and certainly once it's in the car you can't tell at all - the slight difference really only shows up in photos. Likewise it matches well against the new A/B/C pillar trim I bought (which fortunately all match each other as well - as that was a problem for a while): While the headliner was out I took the opportunity to pull out the wiring a PO had put in for a radar scanner - I removed the T-Tap connectors, insulated the wires and wrapped in Tessa tape: In order to remove the sunroof cover to retrim it I also had to remove the sunroof glass - I took the opportunity while it was out to give the frame a good clean and re-lubricate with graphite lubricant: I reinstalled the headliner and then got on to installing the new pillar trim - shiny new B-pillar covers: Then the C-pillars, along with the foam insulated clips: And lastly the A-pillar trims and inserts with the airbag logo on them. Notably the A pillar inserts are a significantly different shade to everything else. (which is hilarious given this is all new OE parts). If it annoys me too much I might order replacements and hope for a better match. I'm very happy to have this done - it's not a particularly fun job but very satisfying to have everything refreshed and like new. You can see the huge difference in shade between the new a-pillar and the insert 🙄.

Well 2 days of driving an excavator, 4 months of weekends, 300m of rebar, 14 tonnes of concrete, 232 CMU blocks, and a lot of manual labour my retaining wall is complete - finished backfilling it today. Starting to get a bit wet here for the winter so great timing. Bit of a general update on the car. The latest version of the SMG reservoir bracket is in use, I've got some more tweaks to make to it so will do that and print the latest iteration. The MAP sensor adapter in CF-PETG shows some evidence of softening. It seems, under the clamping force of the bolts, it's not quite up to the ~100 degree C temperature that the rail hits. Plan is to get this printed in GF-Nylon which should be able to handle beyond 150 degree C temps. I'm doing some preliminary work on the reinstallation of the trunk interior with the RACP brace in place. Working through a few things to get to a lightweight, high-quality solution that meets my need to make it look as OE as possible. The version of the CSL tune I've been running the last while seems super stable. Even as it's got colder here it's remained super smooth. Seems I've got the warm-up maps pretty much spot on. I still want to do some more fine-tuning, and in particular am keen to try out running the fuel tuning process with the MAP sensor integrator turned off, but it's not top of the priority list given what I'm currently running is so good. Planning to get the headliner out and off to the pros to redo with the BM-134 fabric that I have stashed. I've also got brand new A/B/C pillars to go in once it's reinstalled. Intend to make more progress with the 0401 disassembly as well - especially as the days get shorter and the weather gets worse. Lots of little bits and pieces on the go. I've also been enjoying driving the car. The refreshed diff bushes have eliminated any remaining clunk in the drivetrain. Combined with the smoothness of the CSL tune it makes for lots of enjoyable downshifts with no need for the manual throttle modulating that I'd previously gotten used to to minimize the thunk. Secondly the RACP brace has, in addition to providing top-side support to the RACP, made an enormous difference to the torsional rigidity of the rear of the car. It's a very significant improvement and I'm getting itchy to give the front of the car similar treatment 😛

pretty sure this breaks moderation rule #18...

Today I also finished up the repainting of the v brace and rear sway bar brackets project. I top coated them a week and a half ago and they've been resting while the enamel fully cured. Today I reinstalled them along with new hardware to match.

Another rainy day here so retaining wall is again on hold. I took the opportunity this morning to finally redo the matte screen overlay on the Xtrons head unit. I got the Xtrons about 16 months ago and have had a much better experience with it than I was expecting. I'm well decided that I'll be keeping it. one of the downsides of it, and many head units is the glossy screen. About a year ago I purchased a matte screen overlay to see if I liked it better. I did my best to line it up nicely but because I had to cut it to size the edges were visible and annoying to me. I've long intended to take the head unit out and disassemble it so that I could replace the overlay over the entire LCD screen so that the edges would be hidden by the bezel if that makes sense. Today was that day. Head unit out: Rear case off: Disconnect the two big ribbon cables between the chassis and the display and remove the 4x screws holding the display shield on. Then the display and shield pop out of the bezel: The screen with the old matte overlay on it: Old matte overlay removed: I didn't get any photos of applying the new overlay as both my wife and I were employed in getting it on and keeping the screen completely free of dust. We succeeded and the overlay went down perfectly: The new overlay with the protection layer removed: Then it was just a case of reinstalling back into the bezel: And reconnecting the ribbon cables and putting it all back together: I'm super happy with how this has turned out - we got the overlay to go down perfectly and it looks fantastic: While I had the unit out I took the opportunity to plug in the USB extension and install the latest firmware to address the issue with a greater than expected difference between volume levels 4 and 5. This was straightforward and did indeed fix the issue. Now that it's reinstalled I'll give the screen and the head unit a clean to get the fingerprints from install off. Good, quick rainy day project 🙂

Sill waiting for the ground to dry out a little bit before I progress the retaining wall so spent a couple of hours this afternoon taking the rear sway bar brackets and v brace off and cleaning them up. When Dad and I did the underbody refresh in 2017 we used an enamel black paint for most of the pieces, and 8 years on they still look amazing - wipe the road dust off and they look brand new still. There were a couple of pieces (the sway bar brackets and v brace) which we painted with exactly the same stuff, only silver instead of black. Unfortunately the silver kind of sucks in comparison to the black - presumably whatever they put in it to make it silver makes it more susceptible to surface rusting. So anyway - I took them off, stripped the enamel with acetone and then cleaned up the surfaces with some fine sandpaper before cleaning again with acetone and then undercoating. The pictures are a bit average because it's pretty late in the day here, but I'm sure you've all seen undercoated things before: Had something interesting happen when I was spraying the undercoat on. It went on beautifully and then I noticed along some of the edges that it looked like it was bubbling. *Cue confusion*. The surface was prepped well and was very clean so I wasn't sure what was going on - I've used this undercoat a bunch of times and it's always been lovely. Closer inspection revealed it was moisture beading on top of the paint. Actual paint surface is fine and the moisture evaporated again. I'm guessing that it must be close to dew point here right now and the propellant from the spray paint has cooled the surface of the metal just enough at the edges for moisture to condense. Anyway - the moisture evaporated after some minutes and the paint surface seems good. I'll double check it when it's set to make sure it has good adhesion.

I realised I never really updated on the bracket for the SMG reservoir. Since I installed the CSL airbox I've been running a prototype version of the bracket. Given it's a rainy Thursday here I thought since I'd proved the concept that I'd design up a more final version of the bracket. This is still a development version and you'll note there's a few things that need to be tidied up, but didn't want to go to too much effort until I've confirmed fitment of this latest version. I started by using my previous prototype to confirm the location of the bracket itself and mark where I wanted it with some blue masking tape. I then scanned the strut tower and loaded the (fairly untidy) mesh into Fusion to help with placing reference planes, etc. Because the tower is an irregular shape the bracket needs to account for this: Note that the final unit will have rubber stand offs on the back to help it sit well on the tower and not rub. The mounting point where it's attached to the stud on the strut tower also has a raised, angled boss as the stud is not perpendicular to the strut and this needs to be accounted for so that the nut clamps the mounting point properly. I'll get this version printed up and do another round of test fitting and any final adjustments before I tidy up the rough edges. Given my goal of not wanting to drill holes in my strut tower I think that this should be a pretty tidy end result.

Torrential rain yesterday and today so I can't do any work on my retaining wall at home. Got round to a little job I've been wanting to do for a while. The trim around the SMG shifter boot makes an annoying plastic on plastic creak sometimes when shifting, which isn't particularly pleasant from a driving experience point of view. Today I took the trim apart and used some tesa tape to insulate the clips and mating surfaces. I also gave everything a good clean while I had it apart. Put it back together and the squeaks are completely gone (unless I press very hard directly on the plastic trim), shifting is now a satisfying mechanical click, rather than the annoying creaking sound it could be before.

Had a great weekend working on the car. On Saturday morning Dad and I got the car up on stands and exhaust and driveshaft out. Unbolted the exhaust at the headers and dropped the whole thing, then the same with the driveshaft. So much faster than last time given we're just removing and reinstalling rather than taking it all apart to clean. I'm super happy with how everything under the car is holding up, it's 8 years since we did the underbody refresh and everything is looking really good under there. I did the new gear position sensor first, access is a bit of a mission but the mutilated allen key approach does work. The old sensor was extremely notchy and rough after 20 years of service. Worth noting that we ran the first part of the SMG adaption (up to the point it wants the car started) to make sure it was happy with the new GPS. After that we moved on to lowering the rear subframe to facilitate the installation of the Yurkan Cages 6 point brace. We took off the brake calipers and rear trailing arm pockets and lowered the entire thing about 100mm on a couple of jacks (to give us more control over forward/rearward weight distribution). That gave us enough access to unbolt the front RACP studs and get them out. We then jacked the subframe back into place and loosely bolted it, which gave us a better safety factor while working under it. At this point we drained the diff, swapped out the rear diff cover for a new one and reinstalled with new bolts and drain plugs. I've mentioned previously that I'd long experienced some clunkiness when shifting/loading/unloading the drivetrain. This was vastly improved by adapting the SMG. I wasn't sure whether what remained was the diff getting a bit tired or whether the rear bushes needed replacing but I was pleased on checking the diff that there is no detectable lash in the diff at all, likewise with the driveshaft. I was therefore pretty hopeful that it was just the rear diff bushes that were the culprit. The rest of the process was pretty straightforward, we unbolted one point at a time and using a threaded drill guide that dad turned on his lathe and an extra long 6mm drill bit we went up through each of the 4 points in turn. Then it was simply a case of come down from the top with a 10.5mm bit before running a tap on a long extension up from underneath to complete the thread the whole way through. With that done it was then a case of bolting in each of the 4 points and torquing to spec. The rest of the reassembly took a couple of hours and we had the car on the ground again. The install of the brace was super quick - fitment of the brace was absolutely perfect - Marin's fabrication is spot on. Then it was just a case of running the complete adaption on the SMG and going for a test drive. Today I drove the car on a route I'm very familiar with and I'm extremely pleased with the end result! The last of the clunkiness when shifting is now resolved. Even under heavy acceleration in S5/S6 all you get is the sound and surge of power. I'm super stoked. And the brace. Well, I know others have reported a big improvement, but I wasn't completely sure if I'd find the same. Suffice to say the improvement is not subtle! For me the rear has always felt slightly less co-ordinated than the front (not to say it's not objectively excellent to begin with, but it's always stood out to me that the car is just a little bit more put together in the front). Now with the brace it's the other way around! The change in stiffness is hugely noticeable even just driving around town. As soon as you get to a roundabout or uneven tarmac it becomes very apparent how much more rigidity there is. The car really feels glued together in the back now. I love it and am excited to go for a decent spirited drive.

Yeah it's working well for me - took me a little while to load in what stock I have on hand. I think I've still got the load files somewhere with all the different part numbers etc. if you like I can dig it out for you - help save you some time 🙂

I was back to work this week running v5 of my tune with 5 rounds of VE tuning on top of it. It's given me the opportunity to drive a familiar route and get some good comparisons, as most of my recent driving has been VE tuning runs. Firstly - low rpm, round town drivability is now, believe it or not, BETTER than it was for me with stock airbox and stock program/tune! (to be fair I also cleaned the TBs, ICV, etc. at the same time so need to consider the impact this will have had also). Needless to say I'm extremely happy with how this is turning out. Drivability concerns are what put me off doing the CSL airbox for so long, so I'm stoked that this approach has turned out so well. I'm not sure if it's that just my car wasn't completely happy with the standard 1901 tune my car came with or what, but I guess I'd got used to avoiding certain RPMs at certain loads and speeds and all that is gone. I can cleanly and smoothly run up and down the range in first gear in stop start traffic, I can stay in higher gears at lower speeds than I would have and it's smooth sailing. SMG shifts and downshifts are excellent and repeatable. On the euro software (both with and without the CSL255 parameters) I couldn't be completely confident that I wouldn't get a bit of a jolt sometimes downshifting from 2nd to 1st with my foot off the accelerator. Now all that is gone completely. Not to make out that there aren't still improvements I can make, there's a couple of rpm/load spots I need to smooth out some more, but there's not many of them left at this point. Another scenario I often encountered previously was the tendency for the car to jerk under anything more than mild acceleration for the first 30 seconds or so after startup when completely cold. That's gone as well and drivability is smooth from completely cold. When starting out with this I would have been stoked to have ended up with the drivability being no worse than it was on the Euro tune, to have ended up with something even better is magic. I'm looking forward to continuing to fine tune. Relatedly I've been making some good progress with disassembly and have started looking at options around pushing more useful values onto the CANBUS. Looking at the address tables, functions, etc there doesn't seem to be any particular reason why it wouldn't be possible to add a function for an additional ARBID to be inserted onto the bus. If given an appropriately low priority ARBID it shouldn't get in the way of more critical signals. The bit that would be most difficult to figure out (apart from the bit where you DON'T brick your DME) is the easiest way to inject the additional function call into the flow. Looking at the 10ms task it would probably be easiest to take an existing function, move that function and use it's original address to build out a new function that calls both it and the additional function for the new ARBID. Unless I can find some spare bytes somewhere to inject an additional JSR (no doubt there's others here with more skills than me at identifying injection points for patches, so sing out if you have any suggestions). Other pre-reqs to this include tracing the variables that would be useful to send (things like lambda integrators, rpm, relative opening) and following the program flow to confirm the actual internal refresh rates for those variables (some of these are defined in the funktionsrahmen, but some aren't so I'd like to confirm for peace of mind).

After a few days of Mr Three being in hospital we got him home yesterday morning. Yesterday evening and today I tested v3,4 and 5 of the tune. 3 and 4 were duds (in comparison to v2) in various ways (pushing the boundaries of the theory covered above too far, but on the plus side helping me get a feel for the various adjustments) but I’m very pleased with how v5 has turned out and am happy that I have a good base now to build on. To that end I ran the first round of logging for VE tuning this evening as the tune is currently rich across the board. After a few rounds of VE tuning I’ll then start making fine adjustments to the tune as needed once the larger adjustments are out of the way. I managed to force some pinging under heavy load from about 1100rpm, which is interesting as I’m entirely Euro tune in that range so would be interested to know if that happened on my original tune as well - I don’t recall having come across it before. But aside from that it’s feeling good.