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  • 1981 B7 turbo

Just about a year ago.....

Updated: Aug 31, 2019

The first time I saw the Alpina B7 in the flesh (metal?) was a year ago. Less than a month later, I made this web site. Since then not much and a lot has happened.

After getting the car, I did some sleuthing and found out that I was wrong and that the B.A.R. sticker did mean, if I could get the beast to pass smog, that it could be registered in California. Shortly after my initial post here I tried to smog the car at my local smog station. The guy knew me well from my many, many efforts to get my 1996 Porsche to pass the sniffer test. He slipped the Alpina in the little room where the machine is located and proceeded to test away. The car failed. Badly. So badly it was labeled a “gross polluter.”


Back to the drawing board, I started looking for someone local that could tune the car and put a cat on it help clean up the emissions. The best suggestion was to take it up to Sacramento to my friend’s shop there. He knew old BMWs, knew how similar fuel injections worked and was an old-school mechanic who actually knew how to read plugs and diagnose cars – he wasn’t a modern “mechanic” who simply replaced parts the computer told him had failed. But he was not my first choice because my other Alpina (an e21 C1 2.3) was already at his shop and he has a business to run and only so much time for projects likes this. If he took on this project then the C1 2.3 would fall lower in priority.


When I dropped the car off in Sacramento there were a few other issues I asked him to address, like the difficultly shifting and a sticky clutch pedal. And, more importantly, on the drive to his shop I found it nearly impossible to fill the tank with gas because of the vapor-catching accordion on the nozzle. Alpina had raised the gas filler neck about an inch from stock (presumably) because of height of the auxiliary tank and that left no clearance for the accordions. I bought a plastic gas can, filled it and poured it's contents into the tank. But I knew this was not a long-term solution. So, he had a nice punch-list of items for the B7. It was early September of 2018 and I hoped to get the car back in a few weeks, maybe a month or two.


I got the car back in early August 2019, a few weeks shy of a year after taking delivery. Had I not insisted that I get it back before Monterey car week so I take it to Legends of the Autobahn, I suspect it would still be in Sacramento, slowly getting fixed. Worse yet, while the car was smogged, it was not dialed in. It ran. It ran ok. But it didn’t run right. He warned me that the car leans out on boost above 5,000 rpm and upon driving it home I discovered that, once warm, the idle was difficult. Over the few days I had driving it home from Sacramento and then to (and around) Monterey, I was able to adjust the idle mixture so it was trackable but the lean-boost problem was/is still there.

What took him almost a year to fix on the car? A lot considering the car barely ran any better than when I dropped it off. A new exhaust was made, with a cat. The fuel injection was tweeked to get the numbers right, and I had a smog-compliant car! Sounds simple, but just that step took several months.



old exhaust


new exhaust and cat


On to the next steps. The clutch was sticking and if was hard to shift. So, the transmission was pulled, a new clutch installed (correctly, unlike the last clutch) and the short-shift kit adjusted to a more acceptable throw.

While under the car, it was discovered that the lowest part of the turbo plumbing was smashed in. A new piece had to be fabricated, which, of course, took time.

With the new turbo plumbing installed, it was time to get the car running better and clean up some ugly prior repairs. First up was the cooling system. The radiator had been hit by the fan some time ago and the “solution” was to JB Weld the hole. That was unacceptable and the radiator was recored.



stupid-ass radiator repairs

But to do that, the control pressure regulator had to be removed. Simply removing the control pressure regulator was a chore. It had been taken off before and whomever put it back on used gasket sealant that wouldn’t allow it to be separated from the coolant manifold. The manifold had to be destroyed and a new one sourced.



old manifold with regulator plate (blue) glued in place


destroyed manifold


new manifold assembled

The differential cooler had no belt, so one got sourced.




And then there was a slight leak around the injectors, which are held in place by a custom plastic NLA Alpina part. Those had to be fabricated.


old, cracked, and discolored injector holder

new injector holder 3D printed

The throttle position sensor needed adjustment.





Once all that was done, a spirited test drive was in order. That was great until the diaphragm on the control pressure regulator failed. That piece is one of the two or three items that is at the heart of the very rare and unusual Pierburg fuel injection. We looked into Pierburg or Alpina rebuilding it and it was possible. Indeed, Alpina had sent one to Pierburg to be rebuilt, a mere seven months earlier. But Pierburg was not giving any estimate on when it would be done, even after 7months! That wasn’t an option, so my friend opened it up himself and, after contemplating how to rebuild it (and talking to several others), he used parts from a Weber carb rebuild kit to fabricate a new diaphragm. That was in April.



control pressure regulator


deformed control pressure regulator diaphragm


control pressure regulator rebuild


As you can imagine, it took time to get the thing rebuilt and running close to right. Had I not promised myself to take the car to Legends, it would undoubtedly still be in Sacramento, getting fine tuned. But, promises are promises, even if they are really just artificial deadlines and only promises to ones self. I picked the car up on a Wednesday and drove it home. It was 105 in Sacramento and got as low as 97 on the drive home. The B7 has air conditioning, which is great. But it hasn’t worked in years and did nothing, so the windows were down the entire drive home and it was sweaty and hot.

Thursday, down to Monterey, where for the second day the idle was funky. Thursday night test drive and some idle mixture tweeking got the car running moderately acceptable. Friday morning, off to Legends and then, after the show, back home.

The drives from Sacramento back home to the Bay Area, to Monterey and back home again revealed a nice punchlist of work that needed to be done. Some things were already known, like the little surface rust on the hood and around the rubber gasket for the trunk and the seats needing new fabric. Added to the list is getting the fuel injection dialed in – if it can be with the control pressure regulator in it’s current condition – and the air conditioning operating again. Also on the plate: replacing the (incorrect) Alpina stripes and buffing out the paint. If I can get those thing accomplished, I think it will be a pretty nice car…..



My B7 (right) at Legends -- and another for good measure

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BaT side view.jpg

Email me at info@alpinac1.com

Check out my other web site:  www.alpinac1.com

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