A Brief Synopsis/Guide to the Auto -> 6-speed Swap

[cer54467]

Did you put the center mid section trannymounts in? The mount on one side is actually clamped to the exhaust and i have the original piece but it is kind of rotten/ twisted because not much structural integrity left. Do you have PN for this?

[Bryson]

I actually didn't put in the exhaust mounts that bolt to the tranny, I went with a custom solution instead. That's a good point, I should add those parts to the swap list.

Thanks

[cer54467]

I was thinking about amking a custom aluminum bolt on piece but i was concerned about heat transfer.
Are the OEM ones still available?


Do ya have a pic of what you did?

I actually didn't put in the exhaust mounts that bolt to the tranny, I went with a custom solution instead. That's a good point, I should add those parts to the swap list.

Thanks

[Bryson]

I wouldn't be concerned about heat transfer, those ears on the transmission are sufficiently far from the transmission internals that you shouldn't notice any ill-effects.

I actually used only the normal U-shaped exhaust hangers, but filled the cavities with 80A urethane. The exhaust is now firmly held in position and I have not noticed any increase in NVH at all. I'll try to snap a picture the next time the car is in the air, I was in a hurry when I installed them.

[cer54467]

Actualy i have to TIG one of the tranny mounts back on the tranny as it was snapped off. I am more concerned about heat transfereence from the exhaust to the rubber mount and makin it a gooey mess or starting it on fire.

I wouldn't be concerned about heat transfer, those ears on the transmission are sufficiently far from the transmission internals that you shouldn't notice any ill-effects.

I actually used only the normal U-shaped exhaust hangers, but filled the cavities with 80A urethane. The exhaust is now firmly held in position and I have not noticed any increase in NVH at all. I'll try to snap a picture the next time the car is in the air, I was in a hurry when I installed them.

[Bryson]

I can't say that I'm an expert here, but I imagine that as long as the mount is ~3"+ from the exhaust, you'll probably be fine. Why not make it out of steel like the stock ones?

[cer54467]

Have aluminum and easier to work with. I need new tooling for my Mill and i keep spending my money on 6 speed swaps and painting the csi stuff.......

[Bryson]

Well at least you've got your priorities sorted

[Bryson]

Original Post updated with photos of electrical work

[firebird540]

Great post. Thanks for the effort!

The TRANS FAILSAFE error you work around is only due to the lack of the shift lock solenoid, yes?

Tony

Tony,

this 6speed manual mod description is for a M70 V12 5.0L. There would be more involved for a M73 manual convertion (you could not remove a M73 EGS 9.22 and just use the M73 DMEs and EML IIIs - they are exchanging data via the CAN bus and if this data is not exchanged the DMEs for example pull back some parameters like ignition...)

On M73 you have to simulate the shift lock solenoid on my mod.

cheers
firebird

[Fatandre]

Why did you order the lever from a z3, not from a e31?

[Bryson]

I ordered the Z3 shift lever(s) as an experiment for an OEM short shifter. The lever from the 2.8L Z3 had about the same throw as a stock 8, while the MZ3 was about a 25% reduction. It bolts right in and is cheaper than stock by a good margin I prefer it to the aftermarket (UUC, etc) after having owned both types

I'm using the MZ3 lever and would highly recommend it.

MZ3 Shifter Part Number: 25-11-7-527-254, dealer list $69.98

[thelongeride]

Thanks to the members here...and to Bryson. I now own a 1991 BMW 850 six speed.
I completed my 6 Speed swap. This entire job can be done by one person with a little planning!
The instructions and advice were good enough for a newbie to follow. The factory fresh transmission was from Bret Anderson. The parts were mainly from Charlie Spear at Gault. (other sourcing for certain parts)
Drive shaft balancing by Marty of Long island Drive Shaft.
With a 3.15 LSD, semi-custom suspension and Wokke chips the car is a blast.
The instruction and support came from anyone posting here. Thank you.

[Bryson]

Congratulations N! Time to go have some fun

[moutine]

What a interesting post! I have allways wondered how to solve electric on automatic based car but looks like it is quite simple.

How hard it is to find manual V12 trany? Any new units still awaible?

[thelongeride]

What a interesting post! I have allways wondered how to solve electric on automatic based car but looks like it is quite simple.

How hard it is to find manual V12 tranny? Any new units still available?

I may have gotten one of the last new units here in the US. Brett may be sourcing more. In Finland may be a different story.

[wokke]

What a interesting post! I have allways wondered how to solve electric on automatic based car but looks like it is quite simple.

How hard it is to find manual V12 trany? Any new units still awaible?

Some members of 8er.org bought the last new units from Getrag directly. So no more available via official channels.

[Omega man 1969]

What a interesting post! I have allways wondered how to solve electric on automatic based car but looks like it is quite simple.

How hard it is to find manual V12 trany? Any new units still awaible?

I have 2 new units if you're interested.

[B10 BITURBO]

I have 2 new units if you're interested.

The coolest purchese ........... EVER

[e31bev]

Hi Bryson, can you tell me what was the most difficult part of the swap?

[Bryson]

Definitely collecting the parts

[clockwork]

Awesome write-up and resource, thanks for posting all this Brandon. Maybe one day I'll get around to doing this...

looks like that day came.... oh wait NOPE, you just bought a tt with standard tranny haha

[JimmyBones]

Great thread!

Has anyone rebuilt one of these six speeds?

[Prometheus]

I'm not sure why this didn't pop up when I used the forum's search function...

This a wealth of onformation & I want to say THANK YOU!

[rob0r]

I've been looking for a definitive guide on how to convert an M70 over to manual, I've just found it. Fantastic information!

I've bought an 850csi engine and 6 speed, it will be going in an E32 750i