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Re: BMW 325ix 4 wheel drive ?

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From: /DDV2=u3520170@au.ac.th/DDT2=MBX1/DDV=INTERNET/DDT=EMS/S=Benjawan Kuecharoenwong/A=MCI/C=US/ at ccmgwy
Date: 4/18/95 1:25AM
Subject: Re: BMW 325ix 4 wheel drive ?

About this 325ix, I heard a lot of good things and very little bad. That 
could be a little bias coming from a BMW owner(535i). Witht he ix, you lose 
a little straight line acceleration and have more drivetrain noise than a 
regualr 325. I know it uses a viscous central diff -about all I know.

Just a point,...  the ix is offered outside the US and have been for a 
while I believe.. It is just not popular in the US (why? :-| )

For more info, send "help" in the body to majordomo@lists.balltown.cma.com, 
then you can get on the BMW mailing list, there's also a home page for BMW 
cars ====> http://cbsgi1.bu.edu/bmw/bmw.html
 if you'r not there already.

Here's some stuff I found from old digests:  (nice quattro tid-pit included)
=============================================  sorry if long ========
From: GAHAINES@aol.com
Date: Wed, 8 Feb 1995 11:22:52 -0500 Subject: Re. Additional 325iX Info

>As I interpret this, then, the 'iX does not wait for the rear wheels to >slip 
to apply torque to the front wheels, rather always drives both front >and back 
with a ~40/60 split, and as needed will send nearly all the >torque to one or 
the other.  Is that true?

Yes.  The front wheels always have some torque transmitted to them.  BMW choose 
this ratio (37/63) because this corresponds to the weight distribution on each 
axle under full acceleration.  This avoids the problem typical of front wheel 
drive vehicles in which the front wheels spin under acceleration due to weight 
transfer to the rear.  Road & Track (April '88) states that "The net effect of 
the center differential is to act as a power-management system, transferring 
engine torque away from the end that is slipping and to the end with greater 
grip; as much as *90 percent* of the torque may be shifted to the front or rear 
as required.  This is done actively, quickly and without the occupants of the 
car ever being aware of it."
Another interesting aspect: EPA milage figures for the iX are 17/23 and for the 
iS18/24.  One might expect more of a penalty for the AWD,  but I recall Audi 
actually advertising that their Quattro system *decreased* overall fuel 
consumption because a driven wheel imparts less drag than a rolling wheel over 
about 20mph.  I've never seen BMW discuss this issue or expliot this in their 

>Last time I was at NHIS for a school, there was a highly modified
>'iX ...(with) it's inside front wheel was doing lots of strange things near 
>the limit - bounding and shaking like it wanted to take off on it's own.

Sounds like this car need a better set of shocks and/or that the front bushings 
were shot.  The front iX differential has no limited slip feature, so it seems 
to me that this problem is unrelated to the four wheel drive system.

325iX Registry
'88 325iX
'89 325iX
'95 M3
'74 X1/9

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Subject: Re: BMW 325ix 4 wheel drive ?
Author:  /DDV2=u3520170@au.ac.th/DDT2=MBX1/DDV=INTERNET/DDT=EMS/S=Benjawan 
Kuecharoenwong/A=MCI/C=US/ at ccmgwy
Date:    4/18/95 1:25 AM

I think BMW doesn't have much experience in 4WD,and 325ix is not popular 
,too. So if think of 4WD car they're Audi and Subaru.
	I test my quattro system by accellarate hard on slippy road,not 
destructive,(not necessary to floor pedal),the car should go straight.