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Old 05-17-2015, 01:00 AM   #21
Rob43
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^ Did you see all the failures that just got reported on the MFactory LSD's ??

Cheap might not be a good deal after all....



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I BUILD SUSPENSIONS (Consult) FROM MILD TO WILD FOR RWD & Xi E46's
Quote:
Originally Posted by RacerX View Post
Nitrous is a little trickier than boost, but it's not the spray that kills motors, it's STUPIDITY!!
I Know How To Fix The Rear "Bouncing" Problem On Your Cheap Coilovers Like: Jom RL FK SE & RK.
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Old 05-18-2015, 06:17 PM   #22
mtbracer
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I have a clutch-type Mfactory diff...not happy with it at all. Had to remove all the springs and put it on 60% lock for the thing to be even remotely free. Still takes more than 200 ft/lb to get it to slip. You cannot set it up for smoothness whatsoever. I am going to be sending it back to them at some point, probably after I buy a different diff. I had this thing in and out of my car 3 times before it would not be a spool diff.
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Old 05-18-2015, 07:48 PM   #23
Rob43
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Quote:
Originally Posted by mtbracer View Post
I have a clutch-type Mfactory diff...not happy with it at all. Had to remove all the springs and put it on 60% lock for the thing to be even remotely free. Still takes more than 200 ft/lb to get it to slip. You cannot set it up for smoothness whatsoever. I am going to be sending it back to them at some point, probably after I buy a different diff. I had this thing in and out of my car 3 times before it would not be a spool diff.

This is very interesting news...

You should Re-post this info in the MFactory thread located in the General forum.

This thread gets Very interesting on page #3,
http://forum.e46fanatics.com/showthread.php?t=1043397



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Rob #43 ITS/ITR/STU, BMW 325I, STU LAP RECORD
SUMMIT POINT WV 1:24:229 SCCA
(DynoDynamics https:vimeo.com/8486878 Dyno Video)
"Chance Favors The Prepared Mind"

I BUILD SUSPENSIONS (Consult) FROM MILD TO WILD FOR RWD & Xi E46's
Quote:
Originally Posted by RacerX View Post
Nitrous is a little trickier than boost, but it's not the spray that kills motors, it's STUPIDITY!!
I Know How To Fix The Rear "Bouncing" Problem On Your Cheap Coilovers Like: Jom RL FK SE & RK.
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Old 05-21-2015, 10:51 AM   #24
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mod please remove
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S54B32 E36 M3 DTA S100 Sedan Street car full swap:
http://forums.bimmerforums.com/forum....php?t=1437471

E30 M20 2,7L Alpina + Euro E46 320D ZF 6 speed install
http://www.e30tech.com/forum/showthread.php?t=110010

Last edited by wanganstyle; 05-22-2015 at 01:41 AM.
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Old 05-21-2015, 11:05 AM   #25
wanganstyle
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Quote:
Originally Posted by Rob43 View Post
^ Did you see all the failures that just got reported on the MFactory LSD's ??

Cheap might not be a good deal after all....


Rob43
"Cheap" ....not often actually cost effective or time efficient if doing something only once is your target
Quote:
Originally Posted by mtbracer View Post
I have a clutch-type Mfactory diff...not happy with it at all. Had to remove all the springs and put it on 60% lock for the thing to be even remotely free. Still takes more than 200 ft/lb to get it to slip. You cannot set it up for smoothness whatsoever. I am going to be sending it back to them at some point, probably after I buy a different diff. I had this thing in and out of my car 3 times before it would not be a spool diff.
The m-factory is a metal plate style clutch type lsd; its design is lifted from much higher market Japanese designed and engineered aftermarket racing oriented differentials. Steel on steel; these are very hard to setup and design for street driving and track; usually they are track only (i.e. kaaz, carbonetics) unless of high end design purpose to be streetable (os giken, cusco hybrid). 20+discs is standard

BMW OEM traditionally uses clutch type lsd differentials with a friction coating on discs like brake pads/rotor. These units work on steel/brake pad type material principle, 2,4,6 disc pairs is as much as one ever needs (4 discs in e46m size holds 1200rwhp drag use).

Much easier to setup internally for street drivability but the cost of these units is sky high. ZF builds only the finest products; Drexler uses zf internals.

Handling and how close the unit is to a spool has to do with preloading and how aggressive the ramp angles are; also the initial engagement setting of the cross bars ->ramps.

If the preload springs are too stiff and the clearances too close the handling will suffer greatly. Might work well for a drift car but not for a circuit car.

To give a hint there is often 0 preload or minimal preload set on dedicated circuit racing cars. The ramp angles mechanically leverage lockup in relation to delta wheel speed; clutch plate materials and surface pattern design determine the lockup characteristics

If item is set for handling the static breakaway force will not be very high at all; I'm not sure if m factory understands the handling dynamics of a BMW+rwd +circuit use; they seem to push the gear type units much harder than circuit.

The m factory clutch type unit also looks rather very similar internally to some Japanese units;

Both CUSCO and OS brand units are extremely smooth and have minimal static breakaway loading; its less harsh and more silent than the factory bmw ZF unit.

An OS giken clutch type unit is also silent, has minimal breakaway load required but also locks up fierce on demand like the cusco.

The BMW performance lsd unit for the new e90/92/f30 is also very smooth around town and good handling; its made by DREXLER for bmw.

Pictured is a cusco hybrid unit with coil spring internals; its really nice to park at whole foods but also grips like a mofo on Thunderhill. Cost? A few m factory units lol

Cheap is not the target goal when it comes to differnetial.
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Billet Original CNC LSD for 188K
http://www.wanganstyle.com/

S54B32 E36 M3 DTA S100 Sedan Street car full swap:
http://forums.bimmerforums.com/forum....php?t=1437471

E30 M20 2,7L Alpina + Euro E46 320D ZF 6 speed install
http://www.e30tech.com/forum/showthread.php?t=110010

Last edited by wanganstyle; 05-22-2015 at 01:41 AM.
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Old 05-23-2015, 08:25 AM   #26
mtbracer
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The Mfactory unit is almost exactly like the low end Cusco unit. The build quality is where it suffers. Mfactory has no diff information available (stack percentages or even fastener torque specs) so the Cusco info can be used for setup.

The Mfactoy unit is very Taiwanese/Chinese...a copy of something that works which was not built with much care or knowledge of how it really works.
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Old 05-24-2015, 11:23 AM   #27
wanganstyle
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Quote:
Originally Posted by mtbracer View Post
The Mfactory unit is almost exactly like the low end Cusco unit. The build quality is where it suffers. Mfactory has no diff information available (stack percentages or even fastener torque specs) so the Cusco info can be used for setup.

The Mfactoy unit is very Taiwanese/Chinese...a copy of something that works which was not built with much care or knowledge of how it really works.
I would guess Mainland china for mfactory wanna be Japanese racing units (with no idea or testing on setup configuration)

Taiwan is much higher end for the most part;

The brembo brakes for Ferrari OEM and Porsche use are made in Taiwan along with all high end carbon fiber bicycles; Driveshaft shop component parts are also produced in the same factory supply network that willwood brakes uses.

I use a genuine cusco unit myself (that was setup by cusco direct in southern california). The handling is supreme; cusco is more neutral than the bmw OEM ZF e36m unit that came out - but puts down more power to the ground.

I suggest you try a high end Japan made unit (os giken, cusco rs mz or hybrid); all setting instructions come in the box (or are online) and the units are easily configured.
__________________
Billet Original CNC LSD for 188K
http://www.wanganstyle.com/

S54B32 E36 M3 DTA S100 Sedan Street car full swap:
http://forums.bimmerforums.com/forum....php?t=1437471

E30 M20 2,7L Alpina + Euro E46 320D ZF 6 speed install
http://www.e30tech.com/forum/showthread.php?t=110010

Last edited by wanganstyle; 05-31-2015 at 01:33 PM.
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Old 08-03-2015, 08:19 PM   #28
Greg H
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I have a 3.46 differential, which was pulled from a 325i, but the input shaft is different from the input shaft on the 330i diff. In fact the 330 has a completely different drive shaft from the 325. Does anyone know what I need to do to get the 3.46 diff to match up to the 330i drive shaft?
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Old 08-03-2015, 11:24 PM   #29
Rob43
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Quote:
Originally Posted by Greg H View Post
I have a 3.46 differential, which was pulled from a 325i, but the input shaft is different from the input shaft on the 330i diff. In fact the 330 has a completely different drive shaft from the 325. Does anyone know what I need to do to get the 3.46 diff to match up to the 330i drive shaft?
Yes, you need to swap all of these parts over from your original 330 stock diff for it to work.



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Rob #43 ITS/ITR/STU, BMW 325I, STU LAP RECORD
SUMMIT POINT WV 1:24:229 SCCA
(DynoDynamics https:vimeo.com/8486878 Dyno Video)
"Chance Favors The Prepared Mind"

I BUILD SUSPENSIONS (Consult) FROM MILD TO WILD FOR RWD & Xi E46's
Quote:
Originally Posted by RacerX View Post
Nitrous is a little trickier than boost, but it's not the spray that kills motors, it's STUPIDITY!!
I Know How To Fix The Rear "Bouncing" Problem On Your Cheap Coilovers Like: Jom RL FK SE & RK.
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