5 Speed swap Q's

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pecsok

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I've begun revisiting the 5 speed swap, as an e12 just popped up for sale locally at a verrry attractive price. Could use the tranny for Leela, front clampers for the 1600 brake upgrade, then sell off the rest......
Now the question: Would I have to use a custom driveshaft, or would the e12 shaft work, providing it's in good cond, or the 4-speed shaft? I'd be replacing a 4-speed. Carls writeup is superb, but not crystal clear on this point.
Also, would I use the e9 or e12 bell housing?
Thanks for any ideas, experiences, pointers, critique.......
 
The E12 driveshaft is ok except for one thing: the center support bearing is about 4" closer to the engine than how it is on the coupe. This means you would have to either make a new center support bracket holder on the body or extend and cut the E12 driveshaft such that it mated with the coupe body in the right way. Or, you can just have the stock 4 speed one cut.

Cutting + rebuilding the existing 4 speed driveshaft shouldn't cost too much, I had mine done for ~300$.

The E12 bellhousing is needed if you want to use the updated clutch slave cylinder design. It is a good idea to do so because the E9 bellhousing has a huge hole in the side for the TO arm, while in the E12 version, it is internal. Means less gunk can get into the bellhousing.

Is your coupe Motronic, or carbed?
 
Exactly the info I was looking for!

Thanks for the reply, x_atlas0. I might just go ahead and cut the e9 driveshaft and put in a new center bearing. My car is sort of a pseudo csi. It was originally a carbed automatic, then was converted to injection and 4 speed by a po. The block # matches the chassis, so its original. The head and intake have 81 or 82 (If memory serves) casting dates on them, so it seems it could be an injection system from an early e12, e23 or e24? Would that make sense?
 
Hm, I see, so you are probably on L-Jet.

I asked about the car's injection system because early Motronic systems got the crankshaft position from a sensor on the bellhousing. If your car used early Motronic, then it would need to use this kind of bellhousing. Since it doesn't, however, everything should be fine.
 
Yes, L-jet!

Kinda off topic, but how do you like that Miller MAF? I'm thinking of getting one for the e28.....
 
To be honest, I haven't had a chance to put it on yet. I worked my tail off on the car all Spring Break to sort out a lot of electrical issues, lighting, and interior work, as I had a show to go to the week after. I made it to the show, but I wasn't able to install the MAF in time. Now, I have to concentrate on university, and I probably won't be working on the car for at least a month. I have too many projects due. The CVT and the VR flight simulator are taking up all my time, and I haven't done nearly enough on the telepresence unit yet.

However, based on the glowing reviews from several people on Bimmerforums, as well as several dyno runs, I decided to go ahead with it. I bought it during the christmas special, where is was more than half off. There are a couple of guys with stock B35's using the Miller MAF system and pushing ~200 rwhp / 220rwtq. Those are superb numbers, especially when compared to just a chip, which was about 180/200.

As a side note, since you will be doing all the 5 speed work anyway, I would highly suggest you snag a short shift kit. I didn't have enough scratch for one at the time when I did my swap. I used to have a UUC equipped car before, and now it is the only SSK I would put on the coupe. It was the best shifter I have ever used.
 
The E 12 drive shaft will work but it is the rear section of the shaft which is shorter not the front (on euro cars anyway) due to the fact that the box is 4" longer that means that you need to move the centre bearing mounting 4" rearwards if you wish to use the E12 shaft.
 
Fitting 5 speed & drive shaft issues--

while cutting drive shaft to fit--would suggest replacing U-joints as they are most likely original and with nearly 30 years of use the "permanent" lube is dried out. You will avoid having to deal with this down the road--sooner rather than later I would suspect--also re-balancing is necessary when re-doing same--I strongly subscribe to preventive maintenance when dealing with these now 33-37 year old cars that have usually passed through several owners--consequently I don't have break-downs, mechanical issues or failures, nor being stranded by the roadside by so doing with the 407,000 mile E-9 to which I give care.

BTW--I have had a short shifter in BLUMAX for 6-7 years--part is for a Z-3--was inexpensive and works fine--got it from Mesa Performance--speak to Jim at Mesa if curious--he is very knowledgable on part interchangability with our E-9's and E-12's as well as '02's and E-3's, etc.
 
I'm also looking into installing a 5 speed, and was wondering what people were using for the trans support bracket - I've seen several solutions but an not sure which is best. I contacted Metric Mechanic and they unfortunately do not make their mount any more but would consider if there were at least three people interested in purchasing one. They quoted $250 but looks like it's built like a masonry latrine, if anyone is interested let me know.
Another idea I have been toying with is to eliminate the sheet metal linkage bracket in favor of the newer aluminum (aluminium) type. The front normally clips into the newer Getrags, but the earlier M3 has a bracket that would bolt onto a 265, the benefit would be that you could use the UUC Delrin bushings and a more updated short shifter. If anyone is interested, I could post a few pictures.

Mark
 
I used the E28 trans support bracket. It was a pretty tight fit, but it allowed me to use both trans mounts. I used it because it came with the trans and the E28 tunnel, I have been told, is the same as the E9 tunnel.
 
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