24V AWD Swap Knowledge Base

[The Dark Side of Will]

Here is the Borg-Warner T-case, my dad's previous automatic E30 T-case and my manual trans E30 T-case:



As you can see, the BW unit is a weeeeee bit bigger.

Other views:

[goarmy]

But nothing wrong with the E30 or e34 case..

[goarmy]

You can deactivate things from the module if needed using a different program than the one mentioned but you need a little German to read it. I have it in my other computer can't remember the name, I will post it up. If anything the system will go into safe mode and run like normal on pre calculated settings but not sure for how long. The ATC300 actuator has to do a mandatory pre run on start up and park.

[MildredGorham]

Very Helping Posts

very detailed reply by @mw044 i am too looking this type of articles

[Nisse Järnet]

Looks awesome by the way! As usual :) I'm also hoping to be able to control it with the SM4 but haven't come that far yet :P

[Nisse Järnet]

I talked to alot of E90 guys and have done alot of research and I haven't found a single ATC300 that broke? Only problem seems to be the actuator motor gears as mentioned.

Some blown 335xi front diffs though..

[mw044]

the problem with the ATC300 is in the gearbox of the electric motor that controls lockup. the worm gears are made of plastic. Yep... guess what happens to them?

Isn't there another one used by the N/A cars? I know the 335i has the plastic gearbox but the 325i/328i has a metal one. Don't know if it's the same transfercase.

That's only one of the problems. I don't exactly know what they broke from the atc300, but it was power related.. those plastic worm gears are problem of "all" atc boxes. Same plastic gears are in this atc700 actuator. I don't think it's gonna be a problem in my case.

Does the clutch control slip like the VC does in the E30 T-case or does the clutch transmit all the torque that goes to the front end?

IE, does it work like the E34 T-case or like the Skyline GTR T-case?

Clutch deliver the power to front wheels so it works like skyline GTR t-case. Rear wheel drive goes straight through the box and front wheel drive is via clutch pack.

I just took the actuator with me and starting to investigate how to control it. I have a pretty good idea about how it functions, but have to test that out.

I will be controlling it with autronic sm4 with hopefully 2d (or even 3d) map (tps/tc slip %) with feedback from actuator. At least that's what I'm hoping for.. :D

Here's pic with actuator bolted to t-case and little more cut out of tunnel:

[The Dark Side of Will]

Does the clutch control slip like the VC does in the E30 T-case or does the clutch transmit all the torque that goes to the front end?

IE, does it work like the E34 T-case or like the Skyline GTR T-case?

[nando]

they are electronically controlled, not open though. it's a clutch controlled by a motor. It uses a limited slip fluid really similar to a clutch based rear differential.

the problem with the ATC300 is in the gearbox of the electric motor that controls lockup. the worm gears are made of plastic. Yep... guess what happens to them?

Isn't there another one used by the N/A cars? I know the 335i has the plastic gearbox but the 325i/328i has a metal one. Don't know if it's the same transfercase.

[The Dark Side of Will]

Anything fits with a sawzall and a welder.
That's what I'm banking on.

Are the ATC300 & ATC700 electronically controlled "X-Drive" units? or are they conventional passive units with open center diffs like the E46 T-case?

[mw044]

MW044 blows up a lot of diffs but hasn't blown up a T-case... yet.

However, this looks like a great way to get a stout 6 speed and a bolt-on T-case.

Does the 335xi use the same trans or T-case? Why the E70 T-case?

Yeah, e30 tc is good. Haven't blown up single one yet.

Actually that is the 335xi trans.. it uses atc300 (as goarmy mentioned), but those are not that good. Heard from 335xi guys that they've had problems with atc300 in chipped 335xi's.

BMW used those in smaller bodied cars, but I'm in luck because e30 is sooo big. :D E70 parts fit very nicely. :D

[goarmy]

I believe its just a larger version of the 335xi. They wanted to use it but do to the space they went with the ATC300

[The Dark Side of Will]

MW044 blows up a lot of diffs but hasn't blown up a T-case... yet.

However, this looks like a great way to get a stout 6 speed and a bolt-on T-case.

Does the 335xi use the same trans or T-case? Why the E70 T-case?

[goarmy]

The E30 TC is strong enough, I believe its the differential that's the weak point from what nando told me.

[mw044]

Looks great man! :D Hopefully you wont hate the increased noice :)
I want to fit a GS6-53 too...

Hope so. :D

More bolt-on stuff here. E9x 335i Gs6-53bz and e70 x5 (6 cylinder) atc700 transfer case (compared to e30 ix stuff):




Very very tight around the seat brachets:



Transfercase actuator not installed yet. Still have to cut the tunnel for that. Also the drivers seat front mounting bolt has to be moved somewhere else. Also have to cut the drivers seat just a little to clear the transfercase. Still doable as I measured earlier. No major obstacles yet. :D






Rear part of the package is still hanging ~2cm too low. Couldn't get it in the correct height because I was too careful not to cut too much of the tunnel.