Short-term E23 project

This is the scruffy car I picked up for the transmission. It seems like there are a lot of great parts waiting to be assembled into something a little less disreputable.

I’ve discovered a few surprises along the way. One never knows what you’ll find with a car like this. The seller offered it to me for a pretty good price, and although towing was fairly expensive, I’m figuring I’ll easily make my money back. I’ll also get some decent parts to use on the other cars, or get into another enthusiast’s hands.

The first surprise was when I looked at the car. The 1985 735i has a 50:50 chance of the superior Getrag 265 being installed. According to BMW, they switched over to the far inferior G260/5 in August ’85. When I checked it out, I confirmed the detachable bell housing, three-section design and waffle-pattern of the 265 gearbox casting. I was quietly thrilled. Those are rugged old gearboxes, well worth the purchase price.

The next pleasant surprise was the engine. I was excited to find the small ‘turbo’ casting mark of an M106 head when I checked the car out. With any luck the whole motor was there too. I confirmed it once the car was delivered: the M106 block is very distinctive due to two knock sensor mounts and an oil drain for the turbocharger. After delivery I’d also pulled the DME out of its little cubbyhole. It certainly wasn’t the M106 DME; just looked like the  ‘normal’ 059 unit originally fitted to this car. However, it had been opened…so I checked and discovered a TCD chip had been installed. These are a really nice addition since the DME will adjust timing specifically for the turbocharged engine. Without the chip, advanced timing can rapidly cause pre-ignition damage at higher boost levels. I’ll have to report back on the turbo, TCD also offers an improved turbocharger. The original compressor wheel is replaced with a larger unit, permitting a bolt-in upgrade. These motors cannot fit the newer turbos without substantial modification to the exhaust manifold.

This process hasn’t been without some problems. While the car started OK, it runs like crap until it warms up, then leaks coolant from several places. The parking brake has been totally removed. Many OEM parts are missing. The car was also upgraded with Summit stainless fuel line. That’s not usually a problem since it’s high-quality stuff…unless it’s been installed poorly. Those hoses abraded the brake lines in two places, the worst was at the hacked-up ABS bypass hard lines. Even moving the car around the driveway was an adventure! The rear diff is OK, but the inner CV joints are both completely worn out. I’m surprised they still hold the driveshafts! One of the front wheels also has a stripped lug bolt. I’ll eventually get that out, one way or another.