$200 rwd conversion - Page 4 - E46Fanatics E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Go Back   E46Fanatics > E46 BMW > E46 Xi Forum

E46 Xi Forum
The E46 XI was produced from 01-05 in sedan and touring body styles. Powered by either a 2.5L inline 6 in the 325xi or a 3.0L inline 6 330xi. Discuss all thing about BMW AWD E46 'Xi' here.

Reply
 
Thread Tools Search this Thread Rating: Thread Rating: 4 votes, 4.00 average. Display Modes
Old 08-04-2017, 08:54 PM   #61
zeroforce
Registered User
 
Join Date: Jul 2015
Location: Wayne, Michigan
Posts: 61
My Ride: 2001 BMW 330Ci
That's pretty cool being able to swap between the two types of drive. I live up in a snow state too, so I feel your pain. Keep up the creativity, and wrenching.
__________________
zeroforce is offline   Reply With Quote
Old 09-11-2017, 06:18 PM   #62
inline.6ix
Registered User
 
Join Date: May 2016
Location: Tacoma, WA
Posts: 8
My Ride: 2003 330xi
Sick

Awesome post man
inline.6ix is offline   Reply With Quote
Old 09-11-2017, 07:13 PM   #63
Manchicle
Registered User
 
Join Date: Jan 2014
Location: Denver, CO
Posts: 121
My Ride: 330xi, 330i, 135i
Transmission: 6MT
Quote:
Originally Posted by inline.6ix View Post
Awesome post man
Haha thanks

As for an update, I'm over 5k miles in with no issues. I swapped my 3.07 rear diff for a 3.46, which is pretty great. I have the matching front diff too, if I want to go back to 4wd.

Any electronics guys out there? I've been researching a work-around for the single stage xi DSC. I found a thread that seems to confirm the later e39 Bosch 5.7 units will bolt right in with a few swapped pins in the connector. I'm wondering if the new unit will bring fully disable-able DSC to the car, or if coding it will force it to act like a normal xi unit.
Manchicle is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 09-13-2017, 07:01 PM   #64
xi46
Registered User
 
Join Date: Jul 2016
Location: Colorado
Posts: 183
My Ride: 2002 330xi ZPP/SP/CW
Quote:
Originally Posted by Manchicle View Post
Any electronics guys out there? I've been researching a work-around for the single stage xi DSC. I found a thread that seems to confirm the later e39 Bosch 5.7 units will bolt right in with a few swapped pins in the connector. I'm wondering if the new unit will bring fully disable-able DSC to the car, or if coding it will force it to act like a normal xi unit.
This is really the last remaining issue to tackle to make this a viable swap so I'm very interested as well. I have other priorities right now, but sometime soon I'd like to look into whether we can just code the DSC unit we have using NCS Expert instead of swapping it with one from an E39. There's a thread where someone with a ZHP was able turn off the system that emulates an LSD using the brakes. I know that's a different unit entirely, but we may have similar options.

If we can turn off our DSC units' longitudinal differential-lock function (braking the slipping axle as previously discussed), then this mod can be done without any risk to drivetrain components.
xi46 is offline   Reply With Quote
Old 09-13-2017, 08:28 PM   #65
Manchicle
Registered User
 
Join Date: Jan 2014
Location: Denver, CO
Posts: 121
My Ride: 330xi, 330i, 135i
Transmission: 6MT
Quote:
Originally Posted by xi46 View Post
This is really the last remaining issue to tackle to make this a viable swap so I'm very interested as well. I have other priorities right now, but sometime soon I'd like to look into whether we can just code the DSC unit we have using NCS Expert instead of swapping it with one from an E39. There's a thread where someone with a ZHP was able turn off the system that emulates an LSD using the brakes. I know that's a different unit entirely, but we may have similar options.

If we can turn off our DSC units' longitudinal differential-lock function (braking the slipping axle as previously discussed), then this mod can be done without any risk to drivetrain components.
I'd be willing to guinea pig if we can get some definitive info on the coding. I recently did my own EU2 tune. The fact that rwd e39 cars shared the same DSC unit makes me hopeful. I'm capable, I just don't have enough confidence in my understanding of coding to dive in without some expert guidance.
Manchicle is offline   Reply With Quote
Old 10-10-2017, 09:54 AM   #66
ROX
Registered User
 
Join Date: Oct 2017
Location: Rome
Posts: 2
My Ride: BMW 330XI TOURING
Quote:
Originally Posted by Manchicle View Post
I've been working on a little side project and I've finally made enough progress to post about it here. I picked up a junkyard transfer case and welded up the planetary gearset inside. Not the prettiest welds, but there are more than enough throughout, and the final re-sealed diff spun smooth as new. With a locked center diff, I can run without a front driveshaft and enjoy the RWD. I swapped it in this afternoon and had a very successful ride home. No noise or vibrations way beyond highway cruising speed plus all the perks of rwd (noticeable power bump, oversteer under throttle, slip when I wanted it). DSC wasn't too happy with me when I did mess around, even with it "disabled", but I risked a few clutch dumps in the rain and got plenty of standing wheelspin. I'm going to unplug the unit soon and see what it can really do. The plan for now is to leave the front diff and axles in, the idea being to swap the old transfer case back when I put my snow tires on. But you never know...

Hi! Congratulations for the good idea

Do you think that it's possible to obtain the same result like in the following picture? I'm thinking to weld all the space inside the red arrow, and completely remove all the other gears (yellow arrows). Because there is no more reason to leave connected the central/front gears (less components, less friction and less heat).

What do you think about?


Last edited by ROX; 10-10-2017 at 05:00 PM.
ROX is offline   Reply With Quote
Old 10-12-2017, 03:04 PM   #67
Manchicle
Registered User
 
Join Date: Jan 2014
Location: Denver, CO
Posts: 121
My Ride: 330xi, 330i, 135i
Transmission: 6MT
I'm not really sure how you would accomplish the extra welds you're talking about, and they seem unnecessary if you're going to start by following in my footsteps. That input gear you're pointing to (red) is already locked in place while in constant mesh with the welded planetary unit on the other side of the case. As for removing the other gears for weight and friction reduction, I thought about it but it seemed like more trouble than it was worth. The outer of the two gears is involved with retaining the front output flange. Removing it would bring up a new problem of sealing the case. Removing the big intermediate gear is more feasible, but getting it out would have required major disassembly of rest of the internals, including pulling bearings, and I didn't want to mess with it. Also, you could end up with lubrication issues without those gears there to carry oil up to the carrier and bearings. But hey, this is all speculation anyway. I say go for it. Tell us how it works out...
Manchicle is offline   Reply With Quote
Old 10-12-2017, 06:30 PM   #68
ROX
Registered User
 
Join Date: Oct 2017
Location: Rome
Posts: 2
My Ride: BMW 330XI TOURING
I will receive the spare transfer case in next few days... I let you know

Last edited by ROX; 10-12-2017 at 06:31 PM.
ROX is offline   Reply With Quote
Old 12-10-2017, 06:47 AM   #69
Manchicle
Registered User
 
Join Date: Jan 2014
Location: Denver, CO
Posts: 121
My Ride: 330xi, 330i, 135i
Transmission: 6MT
Back to 4wd just in time for the first snow day of the year. I put about 10k on the car in rwd with the front diff and axles still in place. No noise or vibrations on the ride home. I'd say this first season was a success.
Manchicle is offline   Reply With Quote
Old 12-10-2017, 11:38 AM   #70
xi46
Registered User
 
Join Date: Jul 2016
Location: Colorado
Posts: 183
My Ride: 2002 330xi ZPP/SP/CW
Quote:
Originally Posted by Manchicle View Post
Back to 4wd just in time for the first snow day of the year. I put about 10k on the car in rwd with the front diff and axles still in place. No noise or vibrations on the ride home. I'd say this first season was a success.

Thanks for the update. I haven’t had time to explore the traction control issue discussed previously, but hopefully sometime this winter so I could try this out during the summer.
xi46 is offline   Reply With Quote
Old 12-14-2017, 06:30 PM   #71
drehart
Registered User
 
Join Date: May 2017
Location: Jackson, CA
Posts: 72
My Ride: 2005 330xi
I was thinking about this recently. My thought was a disconnect like the front axels on the YJ jeeps. But, I am curious now. What happens if you just remove the front drive shaft without welding anything. In the real world, this would be the equivalent of having the front tires on ice, and the rear on pavement. Looking at drawings of this transfer case, it doesn't resemble a differential at all. Again, just curious and looking for a conversation, not a debate. let me know what you think.

The manual states "The transmission ratio of the planetary gearset provides a fixed torque transfer of 38:62 (front:Rear). The output speeds to the frontand rear axle are the same (1:1).

https://www.manualslib.com/manual/80...page=54#manual
drehart is offline   Reply With Quote
Old 12-14-2017, 09:27 PM   #72
xi46
Registered User
 
Join Date: Jul 2016
Location: Colorado
Posts: 183
My Ride: 2002 330xi ZPP/SP/CW
$200 rwd conversion

Quote:
Originally Posted by drehart View Post
What happens if you just remove the front drive shaft without welding anything. In the real world, this would be the equivalent of having the front tires on ice, and the rear on pavement.

If you were to remove the front driveshaft without welding, the front driveshaft output would spin freely and the car wouldn’t move. This is not equivalent to having the front tires on ice and the rear on pavement because without the front driveshaft in place, the car is unable to force power to the rear wheels by braking the front wheels. Our AWD system would be worthless without the DSC module.

Last edited by xi46; 12-14-2017 at 09:27 PM.
xi46 is offline   Reply With Quote
Old 12-14-2017, 10:02 PM   #73
Manchicle
Registered User
 
Join Date: Jan 2014
Location: Denver, CO
Posts: 121
My Ride: 330xi, 330i, 135i
Transmission: 6MT
Quote:
Originally Posted by drehart View Post
Looking at drawings of this transfer case, it doesn't resemble a differential at all.
Totally understandable, if you're looking for your traditional ring/pinion/spider gear setup. A planetary gearset actually acts in the same way. In that pdf you found, look at the diagram of the gearset. The three little "planets" take the place of the spider gears. Power is applied to the carrier that houses them, much like the diff carrier in the rear. In an ideal situation (no differential action), the planets themselves don't spin (like spiders), and the whole sun/planet/ring unit spins locked in unison. Equal output speed to both front and rear, same as equal output speed under normal conditions in the rear. As differential action is naturally induced by the changes in wheel speed front-to-rear (in turns, during loss of traction), the planets begin to spin to allow a speed differential between the sun (front output) and ring (rear output). Same concept in the rear; as one wheel accelerates beyond the other, the spiders provide differential action between the two sides. And just like in an open rear, without any clutches or other gears to limit slip, the planetary gearset is more than capable of providing full differential action and sending 200% speed to the bare front output shaft vs. 0% speed to the still-connected rear.

The "torque split" is the natural result of the sun and ring gears being different sizes. The planets are providing power to the sun and ring simultaneously. When a differential action occurs, the X-many-tooth planets rolling on the Y-tooth ring versus Z-tooth sun creates two different torque ratios, hence the rwd bias. This only occurs when the planets are spinning for diff action, so under normal conditions its really 50/50.

Last edited by Manchicle; 12-14-2017 at 10:51 PM.
Manchicle is offline   Reply With Quote
Old 12-14-2017, 10:24 PM   #74
Manchicle
Registered User
 
Join Date: Jan 2014
Location: Denver, CO
Posts: 121
My Ride: 330xi, 330i, 135i
Transmission: 6MT
In essence, by removing the front driveshaft, the traction of the rear wheels would "hold" the ring gear. Applying power to the planets inside a held ring gear would just spin the crap out of the "free" sun gear. Again, to compare to the rear, if you pull one wheel off and leave the other on the ground, you're essentially "holding" one of the spider gears and sending power through the diff, making the "free" side go extra fast.
Manchicle is offline   Reply With Quote
Old 12-15-2017, 12:57 AM   #75
drehart
Registered User
 
Join Date: May 2017
Location: Jackson, CA
Posts: 72
My Ride: 2005 330xi
Thank you both for the explanations. I appreciate your time.


Sent from my iPhone using E46Fanatics
drehart is offline   Reply With Quote
Old 01-01-2018, 07:57 PM   #76
EvaJuli
Registered User
 
Join Date: Apr 2017
Location: Buffalo, NY
Posts: 182
My Ride: E46 325XiT
I purchased a TC today and plan to do the same conversion.
Plenty of time to wrestle the old TC free while the car is away for the winter.

I will document as much as I can.
EvaJuli is offline   Reply With Quote
Old 01-03-2018, 01:23 PM   #77
Zokiru
Registered User
 
Join Date: Jan 2018
Location: Corinth, MS
Posts: 1
My Ride: 2001 330XI
I just bought a 2001 330xi and my front differential basically exploded the night I bought the car. This should be very helpful. Thank you
Zokiru is offline   Reply With Quote
Old 01-04-2018, 08:38 PM   #78
EvaJuli
Registered User
 
Join Date: Apr 2017
Location: Buffalo, NY
Posts: 182
My Ride: E46 325XiT
Found one from an AT which is the same PN as the MT, and i thought were going for cheaper than ones from a MT.
Not sure about the "adapter shaft" though. If I have a MT I assume I already have that- any ideas?

http://www.realoem.com/bmw/enUS/show...diagId=27_0013


EvaJuli is offline   Reply With Quote
Old 01-05-2018, 08:59 AM   #79
332
Registered User
 
Join Date: Feb 2015
Location: Space
Posts: 187
My Ride: 332
My children, unplug abs brain in drug bin. remove front half shaft, remove tranny, tcase, add a rwd trans, plus this custom trans mount. This custom trans mount is for sale, uses all oem mounting locations on xi's, direct swap. With this custom mount, you can make your xi rwd. I sold my old rwd swap xi, working on a new project. GL, if you guys have any questions lmk. To the guy above me, yes if you have a manual tc laying around you have that small shaft.

Last edited by 332; 04-26-2018 at 08:23 PM.
332 is offline   Reply With Quote
Old 01-05-2018, 12:06 PM   #80
EvaJuli
Registered User
 
Join Date: Apr 2017
Location: Buffalo, NY
Posts: 182
My Ride: E46 325XiT
Where you been hiding with this!!
How much does this sell for?
You fabricate it your self?

Quote:
Originally Posted by 332 View Post
My children, unplug abs brain in drug bin. remove front half shaft, remove tranny, tcase, add a rwd trans, plus this custom trans mount. This custom trans mount is for sale, uses all oem mounting locations on xi's, direct swap. With this custom mount, you can make your xi rwd. I sold my old rwd swap xi, working on a new project. GL, if you guys have any questions lmk. To the guy above me, yes if you have a manual tc laying around you have that small shaft.
EvaJuli is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON



All times are GMT -5. The time now is 09:38 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
(c) 1999 - VerticalScope Inc. All rights reserved.