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Little by Little

May 3, 2021


A lot has happened since the last post in early December. At the same time, it feels like the project bounced around with little coming to completion. During the hour and a half drive up to Sacramento I’d often review the progress in my mind and wonder if it was time for a new post. But there was no arc to a story; plenty was being done, progress was (slowly) being made. But none of the things I’d been working on were completed—the stories had beginnings, some had middles, but no end. And that, I realized, is the story.


Ok, that’s not completely true. There have been a few things that have been completed. The transmission is in and the rest of the drivetrain buttoned up. Some pesky rust was found on the frame rail, ground out and plates welded in to cover the holes and ensure structural integrity. Yet much of the car—the fuel injection, the cooling system, the interior—is still a work in progress, and progress has been slow. And, little by little, it keeps moving forward.


The reoccurring theme with the car, at least in this drive-up-to-Sacramento phase, has been the trying to put together a car that someone else took apart years ago. The transmission exemplifies it: After the motor was dropped in, the transmission was put in—we put the car up high on the lift and lifted in the transmission by hand and stabbed it in the clutch. Once bolted in we realized that we had the wrong rear support bracket (it was from a 5-series) but the transmission was hanging there unsupported; we needed something to hold it up while sourcing the right part. I flipped over the 5-series bracket, which caught a corner of the transmission, barely holding it in place until we got the right part. That took a few weeks: the bracket was NLA and when I found a used one it took awhile to get shipped to my home; it was in the car on my next trip up to the shop.



The NLA bracket


But eventually, the right support bracket was sourced and in the car, followed by a guibo and the shift linkage, clutch slave and a whole bunch of little things, resulting in a completed drivetrain. That was the good news from under the car.


The bad news was I noticed bubbling on driver’s side frame rail. I poked it and it was crumbly, a sure sign it was rust. A couple of hours with the Dremel tool and I had 3 holes in the frame rail ranging in size from a dime to a quarter or maybe even a half-dollar. After grinding out all the rust, the metal was treated. We cut some plates from steel sheet metal and Stu welded them in over the holes. I ground down the welds and primed it.

The plates being held in by tape, ready to weld



The welds ground down and the plates primed


Meanwhile, with the engine in, I started to populate it. First was the wiring, then the fuel injection. For the wiring, I asked a few folks on the FaceBook e21 page for pictures of the routing of the wiring; using those as guides, I laid out the wiring harness and connected the electrical components. That was relatively easy.

The fuel injection was more challenging. The basics of the Bosch K were easy enough but it wasn’t time for that yet. Figuring out the auxiliary air system was not so simple. I had too many parts and not enough space to fit it all. I consulted the parts pictures on Mobile Tradition website, which showed two different auxiliary air systems, one using electricity to heat it and another heated by the coolant. And I had parts for both. The parts catalog did not present it as an either-or situation and I spent a fair amount of time trying to figure out how the two systems worked together. I also wondered why would BMW have both systems in one car?


After consulting with other e21 323i owners, it became clear I was right to question both systems working in tandem; it was either-or and that my car used the coolant-based system when I tore it apart years ago. Later, I figured out that the second system was from the spare intake manifold I had. I could have used either but decided to stick with what the car came with, even though it was more complicated. (An interesting side-note: both systems used coolant as a warming agent on the intake system. The system I call coolant based system has coolant run under the fuel pressure regulator (in pic below) and then to the auxiliary air valve. The so-called electrical system uses an electronically warmed auxiliary air valve but runs coolant through the throttle body, I guess to warm the air as it goes into the intake manifold. Why they wanted to do that, I don't know!)

The coolant based system

The electrical system



The extra intake manifold with the electric auxiliary air valve


Once I knew which system I wanted to use, I needed to figure out the routing of the hoses. With that done, it was simply a matter of attaching the hoses and bolting the actual valve to the underside of the manifold. Of course, I wanted to replace worn hoses—and was both easy and difficult. It’s easy to attach new hoses and to source standard sized ones that don’t have weird twist and turns in them. But some were special order parts, further delaying progress because the only way to get them was from Walloth and Nesch in Germany. For some inexplicable “reason” BMW has a schizophrenic policy on US vendors selling euro-only parts. Some euro-only parts can be sourced by US vendors without any drama, but for others you have to show a registration proving you own such a car—and sometimes after doing that BMW still won’t allow them to be sold here. When that happens, the parts have to be ordered from German suppliers or foreign eBay vendors. If I can’t find the parts on eBay, Walloth and Nesch is often the solution, but given their 49 euro shipping charge, I try to bundle parts into a single order, causing even more delays.

The auxiliary air system installed


Planning ahead—and bundling parts orders—has been a challenge for me, given my myopic approach of simply attacking what is in front of me. I’ve been trying to teach myself to think ahead and, in that vein, I realized I’d need to put in the headers soon. The car had came with SuperSprint headers but they were old and rusty.

Old rusty headers


So, I took them to a header shop and had them welded up and ceramic coated. They look great now. It was nice, too, to do this in advance of actually needing them and not delaying the project while they were getting restored. Score one for the home team!


Restored headers


A bunch of little tasks have been completed, too. For example, the door panels are back on, with the handles, cranks, and arm rests (which were found in the strangest places in the shop). A new radiator and coolant overflow were ordered from Walloth and Nesch; including the 49 euro shipping, they were over $100 cheaper than a US vendor, believe it or not!

The exhaust was just hanging there, without the "doughnut" supports.


Five minutes later (after a week of waiting for the part), it was done. Were it was all that easy!

We all knew that eventually the fuel injection would be installed on the engine and that day finally came. Because of the modifications to the motor, the stock fuel injection wasn't going to keep up with the fuel demands of the mild cam increase and significant extra displacement. So I Frankensteined together a bunch of Bosch K parts that Porsche used on the 2.7 liter euro 911S; that motor put out about 210 horsepower, so it flowed enough fuel for my motor. I also arrived at these parts in consultation with another C1 2.3 owner who built a similar motor.


Because the parts were Frankensteined together, I did a test fit (which I didn't quiet finish yet). But first I had to clean up the remaining parts that I was using. The air box got cleaned and painted. The support base that connects the air flow sensor to the air box went into the media blaster to get cleaned up too.


The support bracket before getting blasted.




The support bracket cleaned and on half of the air box


Bolting the air flow sensor on was straight-forward


Before going further, those components needed to be test-fitted. I also needed to figure out what other parts were necessary to install the fuel injection. A couple more things were ordered and the car put away until they arrive.

Fuel injection test fit


After every session, the car has to be raised up and a very, very dusty e30 M3 is tucked in underneath. Good company!

Alas, the list of things to be done is still long: finish the fuel injection, figure out how to wire in the coil, install the headers, finish the headliner, install the sunroof, populate the dash (gauges, heater controls, etc.) that was disassembled when it was sent to Just Dashes to repair the cracks. Once that is done, it can be fired up and see if the damn thing even runs. Feels like that is months away. My goal was to drive the car to Monterey this August for car week. It feels like that is slipping further and further into the unlikely category….

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