My long-term E24 project.

I came by this car in a unique way. I posted an ad to buy older BMWs, specifying E30 parts in particular. I got an intriguing email from a potential seller, asked if I’d consider buying a complete E24 project instead of the E30 parts I had been advertising. First off, it was red. Other good news: it was a “Florida car” (thus little-to-no rust) and the original motor had been upgraded…with an S38B35. That motor had subsequently spun a bearing, but repairs had been made. It would require reassembly and transport.

Sounded interesting. I went up to see it; as described, the car didn’t have a motor in the engine bay. That is certainly a handicap, but I’m pretty handy with motor swaps. What was left was pretty spectacular. The car didn’t (appear to) have any rust at all! That’s a very unusual thing in the world of E24s. The chassis also had some tasty upgrades (full Bilstein Sport setup, M5 brakes, upgraded roll bars). The car was also fitted with most options, including the desirable power leather sport seats, a Momo steering wheel, rear spoiler, rear sunshade, even an r134 A/C upgrade! In all things, it’s important to see what is there instead of what isn’t.

The owner had bought this car many years ago with the complete M5 swap already performed, making it essentially into an M6. He parked it after the S38B35 spun a bearing, and had decided to cut his losses. The motor had been removed, the crank was repaired, but it was all still in boxes. The Getrag 280 and 3.91 large case LSD were still in the car. Nice parts, very rare and expensive. I was strongly tempted to make an offer on the entire lot of parts. Have you ever heard an S38 wide open at full throttle? It’s intoxicating! However, budget kept my ambitions modestly in check. While an S38 is a lovely motor, they are expensive to rebuild & maintain. They’re also not a whole lot more powerful in American specification than the M30 they are loosely based on. Regardless, I was still a little short on cash. So he suggested a pretty good deal. Would I be interested in buying only the chassis, then remove all M5 parts (including the transmission, differential, brakes, etc.), and assist him with selling them on a commission basis? Sold!

So that’s exactly how the deal went down. I removed the transmission, driveshaft and diff; sold them to a nice fellow out east. The motor ended up being parted out. Several venues were helpful (enthusiast forums, CL, Panjo, eBay). We split the proceeds and I proceeded to look for a decent replacement powertrain. Eventually, I found a donor. It was once a very desirable car: an ’82 635CSi in full European trim, imported via the “grey market.” Circumstances had not been kind. It was a totaled-out flood victim with no title, sitting in a field, infested with vermin. Why would I buy a piece of junk like this? As a car, it was a liability. But as a collection of parts…it had a huge amount of potential. It had only run 117K miles. The Euro “dirty” M30B34 (high-compression/no catalyst) was mated to a rugged Getrag 265/6 transmission with a single-mass flywheel and heavy-duty clutch. A large-case diff would complete the transplant into the American-spec Zinnoberrot.

Well, I had hoped to make one car from two…but that’s certainly not how it ended up. Here’s the breakdown:

  1. My original 635CSi project was a chassis with a suspension.
  2. The motor, transmission and brakes were harvested from the ’82 European-spec 635CSi.
  3. I found a limited-slip differential in a ’99 Z3. It’s the rare Torsen geared type, not the common clutch-type.
  4. Some decent wheels came as part of an ’85 635CSiA purchase. They were 16×7.5″ “Style 5″ ‘basketweaves’ originally fitted to an E32. These updated 16″ wheels are a very popular choice. They’re relatively common and have far more choices for performance rubber than the base-model 14” wheels. They’re also far more economical to replace than the 390mm Michelin TRX tires I bought with the car!
  5. Finally (I hope) a ’91 535i donated the DME/ECU and engine harness.
  6. It needed an exhaust system too; that was a well-used system pulled from an E28 535i at my buddy’s garage. It needs quite a bit of welding but is otherwise sufficient.
  7. I’ve also pulled some electronics from other machines. The injectors were pulled from several scrapyard Volvos. My E23 745i donated an AEM wideband O2 sensor supporting emulated output. The Hella H4 E-Code headlights were part of an E30 purchase I made in Wisconsin. The OEM Alpine ‘pyramid’ stereo head unit is from a scrapyard E34.
  8. Finally, I needed quite a few new parts. The radiator had a hole, virtually all hoses needed replacement, the lift pump was dead, some suspension parts were badly worn and the motor needed many gaskets. I’m sure there was more but you get the general idea.

If you’re keeping count, that’s ten donors. There would have been more if I hadn’t missed out on a few really good deals. These are the best parts I could find & fund; hopefully the sum of these parts ends up being better than the original! Early driving tests have been very promising, but it’s all been put away for the winter. I’ll be back on this project in the spring…when the daffodils are blooming…and the road salt is washed away…late March or early April, I’d presume.