Hello everybody , Im converting my 530i to dual webers

demidestructo · Post by **demidestructo** » Wed Aug 02, 2017 3:56 pm

Hey everybody im new to the e12 but not to bmws in general.

I bought a 1978 530i with the thermal reactors,and i vowed to ditch them. I found some sweet period correct thermal reactor replacement headers by supersprint.( anybody know any info on them?) Im lucky because i live in Michigan close to a place called' Classic Daily'. They do work on older bmws to keep them on the road,the owner is a great guy who helps me alot. He sold me a m30 out of a bavaria,rebuilt with amc head,dual 32/36 weber down draft carbs. So thats the motor im using, i want to ditch as much wiring that isnt needed as possible. I swapped in the motor , pulled the rear pumps and filters,and am running a pertronix ignitor and flamethrower coil.
Now for the part ,I bet some people will not like I pulled off the diving board bumper and fitted a e34 front bumper. I had it painted in the original Sierra Beige and I think it looks awesome,and it dropped some weight. I think it looks so good im planning to ua e34 rear bumper a well.

Mike W. · Post by **Mike W.** » Thu Aug 03, 2017 11:17 am

Welcome to the group! Those carbs were a replacement for the evil Zeniths and provided better drivability, but perhaps with a slight drop in power. I lusted over them for years when I had a Bav before I injected it.

demidestructo · Post by **demidestructo** » Sat Aug 05, 2017 8:59 pm

Drop in power? I dont like that! I read they were supposed to be a little bit better on fuel too which is ok . This car is going to be a cruisin car , i have a little turbo m10 powered e21 to go fast. I love the e12 for its classy nature. It still has the 4 speed, but I have a 260 and im searching for a 5 speed driveshaft.

Lock · Post by **Lock** » Sun Aug 06, 2017 1:58 pm

If you're talking about the Getrag 260/6, there isn't a driveshaft for that gearbox for the e12 as it never came with it, see my 260/6 post in the gallery. I had to join two different driveshafts to make one that would fit correctly. Unless you mean the 265 5-speed, there are stock driveshafts for that.

demidestructo · Post by **demidestructo** » Sun Aug 06, 2017 6:27 pm

Im so glad you told me that, i thought a e28 5 speed driveshaft would work. Im just planning to use the 4 speed now ,but id like to build one of your driveshafts. What the recipe?

RonDwyer · Post by **RonDwyer** » Sun Aug 13, 2017 11:47 am

Pieces of the driveshaft could work. A good driveline welder can put it together and balance it for you. 265 has a proper speedo output on it.

Lock · Post by **Lock** » Tue Aug 29, 2017 9:19 pm

demidestructo wrote:Im so glad you told me that, i thought a e28 5 speed driveshaft would work. Im just planning to use the 4 speed now ,but id like to build one of your driveshafts. What the recipe?

For the Getrag 260/6 into the e12, I used the front of a Dorman 936-360 (for a '83 e28 533i), and the rear from a Dorman 936-591 (for a '79 e12). I spoke to Dorman tech support and they confirmed these driveshafts all use the same yoke so you can just join them together, but you should balance them once you've done this.

CabbageFumes · Post by **CabbageFumes** » Wed Aug 30, 2017 6:31 pm

As a public service announcement, I must broadcast:
Driveshaft ends, both front and rear, are balanced independently. Combining one front with a rear from a different chassis won't affect balance. The only thing to make sure of is to join them by lining up the U-joints, bearing cup to bearing cup, both being shaft cup or joint cup, not one of each. That is the only reason that there are marks to line up the front and rear halves- not for balance, but for flex matching. You could turn the assembly marks 180 degrees from each other, and it would still be correct and not affect balance.

Lock · Post by **Lock** » Thu Aug 31, 2017 1:03 am

Thank you! I didn't get the hybrid shaft balanced as a unit because I'm impatient and just wanted to get my car running. So I lined them up arrow to arrow, bearing cup to bearing cup, the way the original units came.

I had heard some people say they'd mixed shafts and it worked fine for them, and others say you have to balance the two halves as a unit because they are now different weights. I figured if it shook too much I'd take it out and get it balanced. Dorman tech support didn't say anything about balancing hybrid shafts, just that they'd fit.

But there is zero shake or vibration, completely smooth from 0 to 80mph.

I will stop advising people to balance it then, as long as it's lined up correctly.