With the transmission, exhaust, and driveshaft removed, it was time to buy some car parts. This is always my favorite part of any project. Coming home from work with tons of packages on your doorstep is like Christmas for car guys. There was lots to buy for the driveline. The list included a transmission, driveshaft, flywheel, clutch, shifter, shifter linkage, transmission support brackets, giubo, flywheel, and bolts for the transmission. The transmission is where I decided to start since a lot of the parts for the E30 are still available off the shelf. I searched the usual spots like Facebook Marketplace and Let Go for some time and finally found a guy selling resealed transmissions. Buying a used transmission is always a risk, especially off of Facebook Marketplace, but I wanted to get the car running and decided to take the risk. I reached out to him and he confirmed he had one ready to go.
The late model E30, 1987 and later, had two different types of Getrag 260 transmissions. The one I picked up was off of a 325e model. The transmission I picked up was 260.0.1270.90. This transmission differs slightly from the one that came stock on the 325i which is the 260.0.1346.90. The 260.0.1270.90 bell housing is 3/8″ deeper than the 260.0.1346.90 due to a different flywheel and comes with a larger output flange. The seller swapped the output flange for me, which helped seal the deal on the sale. The only thing I would have to change to make the swap successful with using this different transmission for my 325i, would be to get a different throwout bearing. When scanning the forums, I came across a forum that suggested using a thicker throwout bearing from a 320i. The part number is 21511204525 and is about 5 mm longer than the stock throwout bearing. Undeterred, I decided to purchase the transmission. Looking back, I should have bought from a more reputable source but it was the only one I could find at the time. To be fair, I was on a tight schedule since I was racing the birth of my first son’s delivery, so I cut myself some slack.
After checking the transmission off of the list, it was time to start buying all of the clutch and linkage gear for the swap. I picked up a stock Sachs clutch from Pelican Parts because I was warned to not get anything stronger than the stock clutch. After all, the power output I am shooting for with the upgraded engine, would never overpower the stock clutch. I decided to pick up a lightened M20 flywheel from Racehead Engineering. I could have bought a stock flywheel and then had it lightened but this was a cheaper option. Even coming from Australia, I was still only $300 out the door.
I also picked up the transmission bracket with some stock bushings. I picked up a second-hand shifting arm and a Dual Shear Selector Rod from Ireland Engineering. This DSSR is supposed to help get rid of some of the slop while shifting. The DSSR design stems from the M3 during the DTM racing days. It is an upgrade since the original selector rod only connects from one side versus the two sides with the DSSR. I also picked up a new giubo from Ireland Engineering. I would also recommend Ireland Engineering for a lot of these basic upgraded parts. They aren’t the only player in town for parts but they have a good amount of parts to help you upgrade your car. I am lucky too since I can drive 30 minutes and avoid shipping. I love living in Southern California where all the main part suppliers are located. Not only can it save you time by picking up parts but saves on shipping too.
I then needed to get a shift lever. I am a huge fan of short throw shifters. I put one on my E36 M3 and made shifting a lot more fun. There are a ton of options out there. I researched options from UUC and Rogue Engineering and after much research, I decided to go with the Z3 shifter. This is a BMW part that pops right into the E30 shifter arm and is a highly recommended shifter. What was left was the Shifter Arm Bracket. I purchased one from Turner Motorsports because it had a 70A polyurethane bushing to help tighten up the shifting. The sealing rubber shift boot was purchased as well as a new reverse light wiring harness. The wiring harness was simple too because the connection for the reverse light was already incorporated into the wiring harness. No need for modification.
The last few items I needed were a drive shaft and all of the bolts needed to secure the manual transmission to the M20 engine. I found a cheap driveshaft off of Facebook Marketplace and then dropped it off to Ireland Engineering which refurbishes them. A quick trip to RealOEM.com and Pelican Parts got me all the bolts needed to install the transmission. A couple items not shown which I picked up new were the spring clip, brass ball pin, and clutch fork for clutch actuation. I wanted to get new hardware since this was the unreachable stuff after the transmission was installed. I decided to go with a brass ball pin since it is a common upgrade even though I am not too sure it is an actual upgrade since brass is a softer metal and could wear faster than the plastic version. After all of these purchases, I was now ready to install the transmission.
This part of the project was fun and tedious and to be honest, expensive. I was always hesitant to buy the manual swap kits seen on Facebook Marketplace because I always thought they were lacking a ton of parts and this process confirmed it. So if you are in the market for an E30 manual swap, buy the parts yourself. I was quite proud of the progress made and how I had fully wrapped my brain around this swap. Finding all of the right parts and putting it all together took a good amount of research and time. Deciding what to upgrade and future-proof was a ton of fun and weighing my options is what I enjoy doing. I was itching to get this transmission in the car and have it move under its own power but there were a few other items I still needed to work out. I still need to work out the pedal situation and clutch line routing. This will have to wait until the next post. Motor on.