The second post in this thread bought this up, but it seemed like a big ask at the time. We're approaching the number of posts in the S38 sub-forum *just in this post* and I'd LOVE to start getting this stuff sorted out into stickies for each system (Cooling, wiring, mounting, intakes, etc).
We could also start to break out build threads for the (at least) four cars that are going, because I bet this is getting confusing if you don't know everyone.
I'm crazy jealous of that e91... Trevbot kindly forgot to remind everyone that I sold this engine already in a BMW once already.
That being said, here are the random things I've learned in the last 24 hours.
Magnesium and plastic valve covers have exclusive ignition/injection wiring harnesses. The magnesium valve cover has a long tray that fits nicely:
In this harness, the umbilical from the DME enters between cyl 4&5, and then the injection wiring is routed around the back of the engine to the injector rail. The plastic valve cover harness management is shorter, and doesn't fit around the bosses on the mag:
This is a screenshot from a plastic to mag cover conversion video here: https://www.youtube.com/watch?v=5uedpKybBEw&t=1835s and please ignore that the cover is black... he painted it black. that's magnesium. the other thing you notice here is that the wiring crosses over the top of the valve cover instead of looping around the back, and the umbilical *enters* from the back corner. There may be more permutations resulting in even more harness detailing, because the exit location of the umbilical is tied to the side of the car that the DME is on, and several cars came with both plastic and mag cover engines. I think to do this right I'm going to be cracking open the ignition tray and installing the longer (X3 in my case) harness into it, and then using the rear port for the exit. There's no reason for the injector side wiring to pass through that tray any more, which means I can run that harness separately and route it to the DME. I probably don't even have to use my x3 injector harness in that case.
Last night's project after the kids were asleep was rebuilding the intake manifold and PCV:
I'm pretty sure my large DISA flap is shot, so I'm working on that, but luckily it's the easy one to swap so it's not critical path. I learned while doing this that there are two version of the 3-stage manifold. one of them has the single pcv port you can see in the center of the "big tube" above. The other has two ports which immediately Y together (discussion here: https://www.e90post.com/forums/showt...php?t=997384):
Why are they different? who knows. I didn't track down which was earlier or later, or which models, had which one, but it's completely internal to the engine so it was some kind of design revision. If I had to guess I'd say having the port immediately opposite the throttle body caused vacuum issues for the PCV, and a single offset port wasn't ideal, but also didn't warrant a second heater (the difference between the big and small port is the larger one gets a heating element). I ended up with the Y hose in my order, but re-used my single hose. Maybe my intake wasn't original to the engine?
My goal with Habla for the time being is to delay him as long as possible to probe him for detailed pictures of factory installations... he's already done me one favor by posting that underhood shot and reminding me that the wiring tray goes RIGHT over the middle of the engine. I was scratching my head last night trying to figure out how the factory routing worked behind the engine... and this morning I realized that it DIDN'T, which leaves me with that unsightly braid-covered PCV hose hanging over the top of the intake (it connects to the boot just in front of the butterfly valve. It's hidden under the cowl of the e90, but I'm going to have to find a replacement and snake it somewhere else.
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