Xoutpost.com - BMW E53 X5 Camber Options

Contributed by: hayaku

<CENTER>BMW E53 X5 Camber Options

by hayaku for xoutpost.com

December 3, 2005
</CENTER>

A few years ago, my wife greatly enjoyed her 2001 X5
3.0. She constantly praised its braking and handling performance.
Sadly, we decided to trade that in for an ultra pimp mini van with 17
cup holders. We always missed the X5 but had plenty of places to put
our drinks. Fortunately a month ago, we decided to pick up another X5.
We found a gorgeous example in a CPO'ed 2002 Steel Gray 4.4i with
sport, navigation, dsp, and premium packages.

This was my wife's daily car and I pretty much

never drove it. During her first few days of ownership, she complained
about a floatiness feeling at highway speeds. Some sort of
unstableness. The car tracked straight and turned when told to, but it
was an unnerving feeling at speed. Sortly afterwards, a Service Engine
Soon light came on for a Cam Position Sensor. I took the opportunity to
have the local dealer fix the SES issue as well as check the alignment.
The sensor was replaced but the alignment tested to be within
tolerances of the factory spec. The technician indicated that it felt
normal for a 3 year old car. Hmmm...

Since I knew our old 2001 X5 3.0i felt great and
didn't exhibit any of these behaviors over the few years we owned it, I
started looking at options to fix my alignment issue. Fortunately I got
word from Ben Liaw of Rogue Engineering that he had camber plates for
the X5 that were almost ready to launch. We chatted some and Ben had
arranged to ship me a set of plates before they hit the market.

3 days later, a package arrived on my door step just
as Ben had promised. This was a bit early as my lift had not been
installed in my new garage yet. No matter. I needed time to come up
with the test plan anyways. I didn't want to do a simple seat of my pants
viewpoint of what the modification would do. I didn't want to post
something as simple as "These Camber Plates ROCKED!!!" or "These Camber
Plates are just about as useful as a third nipple on a turtle's back!".
Instead I wanted to have something quantitative and qualitative to
report, whether it be good or bad.

In order to come up with the proper test plan, I
needed to understand how the X5's suspension was setup and what owner's
perceptions were on its handling. Several times along the way, I had to
stop myself from doing too much research and investigation as it
becomes non-applicable on a street vehicle or most of the data I was
looking for only meant something to suspension designers and not
regular drivers/owners. More importantly, I had to make sure what I was
looking for had to stay relevant to the X5. Keep in mind that I am not
a suspension engineer by trade nor work for a automotive engineering
design group but rather have an extensive network of highly successful
professional race team engineers as friends that provide me guidance, a
slap on the back of the head when I go in the wrong direction, and an
abundance supply of laughter whenever I ask them questions.

<TABLE border=0>

<TBODY><TR><TD colSpan=3>Here's what I found as a working basis:</TD></TR>

<TR><TD vAlign=top>

</TD>

<TD vAlign=top>The BMW E53 X5

(MY2000-MY2003) utilizes a macpherson strut design with 2 separate
links for the lower wishbone. The top of the strut uses a hat with a
predetermined camber setting via an alignment pin. There are 3 slotted
holes in the strut tower in which to secure the top of the strut to the
car. There is also an alignment hole in which the alignment pin would
fit into to set the predetermined factory camber setting. Yes this
means that if you remove the alignment pin, there would be some
adjustment in camber by sliding the strut hat in the slotted holes.
This is very similar to many other BMW models, known as the "Free
Camber" adjustment.

Please note, the picture on the right is an
example of a Macpherson Strut front suspension setup. This is not a
diagram of an E53X5's suspension.

</TD>
<TD>http://www.xoutpost.com/images/articl...macpherson.jpg</TD>

</TR>
<TR></TR>
<TR>

<TD vAlign=top>

</TD>
<TD vAlign=top>You've all

heard or read about someone complaining about "understeer" in the X5.
That is, the front tires surpass their adhesion limit while the rear
still has traction, the rear begins to "push"; the car will not turn as
much as the steering wheel is turned, sometimes just sliding straight
along. Many people have also commented on how the steering wasn't very
exact or sharp on turn in. All this leads to feeling a lack of
confidence in the stability of the X5 at high speeds.

</TD>
<TD>http://www.xoutpost.com/images/articl...understeer.gif</TD>

</TR>

</TBODY>

</TABLE>

<TABLE border=0>

<TBODY><TR><TD align=left colSpan=2>Before we go any further, lets take a look at what camber really is.</TD></TR>

<TR><TD vAlign=top align=middle>http://www.xoutpost.com/images/articles/252/camber.gif</TD>

<TD vAlign=top>But What is Camber?

Camber is the angle of the wheel relative to vertical, as viewed from
the front or the rear of the car. If the wheel leans in towards the
chassis, it has negative camber; if it leans away from the car, it has
positive camber (see pic on left). The cornering force that a tire can
develop is highly dependent on its angle relative to the road surface,
and so wheel camber has a major effect on the road holding of a car.
It's interesting to note that a tire develops its maximum cornering
force at a small negative camber angle. This fact is due to the
contribution of camber thrust, which is an additional lateral force
generated by elastic deformation as the tread rubber pulls through the
tire/road interface (the contact patch).

The BMW E53X5 macpherson strut design only has 3
points in which the suspension is attached. The lower two are fixed
length arms of a wishbone but do allow for pivot motion. The top of the
strut is attached to the strut tower and has a rubber bushing to pivot
by. The strut itself is the only component that changes length as the
lower two arms move up and down. This means that as the wheel moves up
(compression), the camber is decreased (gains negative camber and leans
inward more) and as the wheel moves down (extension), camber is
increased (gains in positive camber and leans outwards more). The
amount of change is determined on the full length of travel of strut,
limited by its bump stop on full compression and by the droop on its
full extension. The X5, being of an all wheel drive design, has a swing
arm axle in the front. The motion of the front axle is limited and
follows the motion of the 3 connection points of the suspension. For
simplicity sake, we'll leave out the influences of the swing arm.

</TD>

</TR>
<TR>

<TD vAlign=top align=middle>http://www.xoutpost.com/images/articl...hassisroll.jpg</TD>
<TD vAlign=top>

Why do we need it?

For our specific application, the complaint is understeer. As the X5
goes through a corner, the lateral load it takes forces the body to
roll about its roll centers/roll couple. As the chassis rolls, the
suspension gets pushed and pulled and moves up and down at the linkages
and ultimately alters the camber and contact patch on the ground. When
the camber moves enough in the positive direction, the tire sidewalls
can roll over a bit. This eventually causes a decrease in available
grip and understeer ensues as the demand for grip is higher then what
is available.

</TD>

</TR>
<TR>

<TD vAlign=top align=middle>http://www.xoutpost.com/images/articl...ttireprint.jpg</TD>
<TD vAlign=top>

Can there be too much negative camber?

Too much negative camber is a bad thing also. When there is excessive
camber, either positive or negative, you will get uneven tire wear
since the tire is riding on an edge now more so then across the face of
the tire. The size of the contact patch does not change with changes in
camber. This is a common misunderstanding. Rather the shape of the
contact patch changes. The area of a contact patch is determined by how
much weight is on that tire. When you have excessive camber, the shape
changes to a tear drop instead of an oval. A unevenly shaped contact
patch will have decreases in braking, acceleration, and cornering
ability. The oval shape covering the entire width of the face of the
tire will give you the most evenly distributed grip. The picture on the
left is an actual tire print of my rear passenger tire at the stock -4
degree setting.

</TD>

</TR>
<TR>

<TD vAlign=top align=middle>http://www.xoutpost.com/images/articl...3alignment.jpg</TD>
<TD vAlign=top>

So how do we know how much camber is enough?

To make things more complicated, not every corner will have the same
camber requirements. Ideally you have the camber set up so that its the
best compromise for the driving style and road conditions. Professional
race teams use the alignment settings as part of their strategy to win
the race. Race teams would take the temperatures of the inner, middle,
and outer cords on the tires to determine how much camber is needed for
that particular course driven by that particular driver. For our
purposes, we have the guidance of the factory alignment specs and can
work around those to find a setting that is more beneficial for the X5.

</TD>

</TR>

</TBODY>

</TABLE>

Ok, if the X5 was designed with understeer, what can we do about it?

<TABLE border=0>

<TBODY><TR>

<TD colSpan=2>Before we look

at how we can change the understeering characteristics of the X5, we
have to see why it does this. Lets take a very simplified look at the
X5. I'm limiting what we look at because our audience is very wide and
not limited to suspension engineers.

</TD>

</TR>

<TR></TR>
<TR>

<TD vAlign=top>

</TD>
<TD>

The most obvious is the difference of camber from front to rear.
Everyone notices the massive amount of negative camber in the rear. The
extra negative camber allows the outside rear to take more chassis
roll/suspension jacking and still remain in traction without tire
rolling before the front exceeds its traction limit.

</TD>

</TR>
<TR></TR>
<TR>

<TD vAlign=top>

</TD>
<TD>

Another difference is the staggered wheels and tire sizes. Again the
rear has the advantage with wider tires and a wider rim. The offsets do
make the track widths the same according to BMW specs page so track was
not used to induce understeer.

</TD>

</TR>
<TR></TR>
<TR>

<TD vAlign=top>

</TD>
<TD>

The E53X5 has an auto-leveling air spring suspension system in the
rear. At least on my sport model it does. The data to that is a pretty
closely guarded secret and I don't have access to it. So for the
purposes of this review, I'm leaving out spring rates and effective
wheel rates on how that affects the handling of the car.

</TD>

</TR>
<TR>

<TD colSpan=2>The differences in

the staggered wheels and tires are neglible and we typically like a
little understeer so the car is not so on edge that it takes lots of
training and 100% concentration just to go to the grocery store. That
leaves us with the most obvious area that we can address: the
differences in camber from the front and rear.

</TD>

</TR>

</TBODY>

</TABLE>

Currently, we have 4 options to deal with the differences in camber front to rear:

Lessen the rear negative camber alignment

Perform the Free Camber Adjustment on the front

Add Camber Plates: Rogue Engineering or Dinan

Or a combination of the above

For this test, we used my wife's 2002 BMW E53X5 4.4i as the test

mule. The X5 is equipped with the sports package (meaning air
suspension rear) and the 19" Style 63 Y-Spoke OEM rims. Tires are
Michelin Diamaris with about 5/32" thread left. The car weighed in at
4919 lbs with a near full tank of gas.

I found out that the two companies that did make camber plates for

the X5 utilized the same design. The companies were Dinan and Rogue
Engineering. With the latest suspicious claims and products from Dinan
(bulging e46m3 air box, z8 frame fiasco, m5 torque loss, etc) I figure
the best bet was with Rogue Engineering. All things being equal, Rogue
Engineering had the better price point ==> which was what I
selected.

The Test Method

<TABLE border=0>

<TBODY><TR>

<TD colSpan=2>I stated that I wanted this test to be

quantitative and qualitative at the beginning of this article. For this
I need to get a baseline of measurements from the vehicle in stock
configuration and measure the changes as we tried the different
options.

The items measured were:

</TD>

</TR>

<TR><TD>

</TD><TD>camber</TD></TR>
<TR><TD>

</TD><TD>tire prints</TD></TR>
<TR><TD>

</TD><TD>static ride height</TD></TR>
<TR><TD>

</TD><TD>sai</TD></TR>
<TR><TD vAlign=top>

</TD><TD>I did other measurements such as

control arm lengths, mounted angles, compression and extension,
suspension movement, instantaneous centers, etc but those won't be used
for this review as they overly complicate the scope. About the only
thing I didn't do was remove them to weigh each component.

</TD></TR>
<TR></TR>
<TR></TR>
<TR>

<TD colSpan=2>To get accurate measurements, we first set the

tire pressures. Then we used leveling platforms with scales and slip
plates. We lifted the car on my two post lift, leveled the platforms to
each other using a laser leveling system. Then lowered the car onto the
platforms and slip plates and shook it to settle the suspension.

We tested camber with both a rim clamp and the
intercomp camber measuring device directly on the center of the rim.
The center of the rim proved to be flat and true to the hub plane and
gave the same readings as the zeroed rim clamp did. Lucky for us since
that meant we didn't have to waste time with zeroing the rim clamp each
time.

For tire prints, we should have used ink on the
tires. Instead we only imprinted the paper with the dirt and grim that
was already on the tire. Sometimes we had a clear imprint, other times,
it was difficult to see, but you could make out what it looked like. I
went back over the imprint with a sharpie.

Static ride height is measured as the half of
diameter of the rim subtracted from a measurement from the bottom of
the rim, through the center cap, to the lowest part of the fender. This
gives the ride height from the center of the hub to the lowest part of
the rim, irregardless of the tire heights/pressures.

</TD>

</TR>
<TR>

<TD align=middle colSpan=2>

<TABLE>

<TBODY><TR>

<TD>http://www.xoutpost.com/images/articl.../levelling.jpg</TD>
<TD>http://www.xoutpost.com/images/articles/252/level.jpg</TD>
<TD>http://www.xoutpost.com/images/articl...readcamber.jpg</TD>
<TD>http://www.xoutpost.com/images/articl...eadcamber2.jpg</TD>

</TR>

</TBODY>

</TABLE>

</TD>

</TR>
<TR></TR>
<TR></TR>
<TR>

<TD colSpan=2>Changes to the car's handling was measured with

performance runs. 5 runs of each were conducted in each of the car's
various states of change:

</TD>

</TR>
<TR><TD>

</TD><TD>Acceleration</TD></TR>
<TR><TD>

</TD><TD>Deceleration</TD></TR>
<TR><TD>

</TD><TD>Autocross course</TD></TR>
<TR></TR>
<TR>

<TD colSpan=2>Alas, poor hayaku does not have the big budget

for proper test equipment and staff engineers nor access to a dedicated
vehicular proving grounds. Instead, I did the next best thing I could.
I went into ninja test mode. I removed as many variables as I could,
constraint those I had control over and measured what I could.

</TD>

</TR>
<TR></TR>
<TR>

<TD colSpan=2>The performance runs were ran at a local

parking lot and was fairly open. If you are in SoCal and recognize the
area by the picture, please do not tell the security guards who was
screeching their tires at late hours in the middle of the night... they
are still looking for a mysterious dark X5. They are also looking for
some orange cones that are missing from the construction area at the
far end...those could be found in various parts throughout the parking
lot =)

</TD>

</TR>
<TR></TR>
<TR>

<TD colSpan=2>I used a straight area for the acceleration. I

had a starting marker in which to accelerate full throttle from. I used
another point in which to get my top speed as I passed it. I have no
idea what the distance is, but these kept the variables the same.
Timing was irrelevant as I didn't know the exact distance but I would
be able to know if my acceleration did change by my top speed observed.

</TD>

</TR>
<TR></TR>
<TR>

<TD colSpan=2>Deceleration measurements were in the same

manner. I got up to a steady speed of 60 mph and slammed on the brakes
at a marker. I would put an orange cone at the point where I stopped
with each run. Again, I don't have distance nor timing for these runs
but I would know if my distance did change, if any.

</TD>

</TR>
<TR>

<TD colSpan=2>I did not have a large enough area to use as a

skid pad for measuring lateral acceleration (g-force). Instead, I laid
out a simple autocross track without cones around the parking lot and
ran with a stop watch around my neck. These I did have timing for and I
tried my best to include sweepers, decreasing radius turns, esses, etc
and stressed as much cornering ability as I could.

</TD>

</TR>
<TR>

<TD colSpan=2>Sure there is room for error. This is not by

any means a scientific test in a controlled environment with repeatable
results. But the test vehicle is the same, same driver, same course,
same everything except the camber and alignment. Therefore the actual
numbers can only used as gauge to help us see if there any changes and
cannot be used as absolute results.

</TD>

</TR>
<TR></TR>
<TR>

<TD align=middle colSpan=2>

<TABLE>

<TBODY><TR><TD align=middle colSpan=3>Map of the Proving Grounds</TD></TR>

<TR>

<TD>http://www.xoutpost.com/images/articl...celeration.jpg</TD>
<TD>http://www.xoutpost.com/images/articles/252/braking.jpg</TD>
<TD>http://www.xoutpost.com/images/articl.../autocross.jpg</TD>

</TR>

</TBODY>

</TABLE>

</TD>

</TR>
<TR></TR>
<TR>

<TD colSpan=2>The last component of this is a subject

viewpoint. My wife knew I was fiddling with the car but didn't know
exactly what I was up to. She was gone for the entire time during the
installation studying for some test in med school. She did voice
complaints about the X5's handling ever since we got it home. She
complained that the car felt floaty at highway speeds and steering felt
very vague. She thought that the 2002 X5 4.4 didn't feel as stable nor
confident as her old 2001 X5 3.0i. I had only driven the 2002 X5 once
and didn't think much of it. Ever since then she was the primary driver
and I initially attributed her complaints to her being used to the
handling of her previous car, a Porsche Boxster S.

</TD>

</TR>

</TBODY>

</TABLE>

The Results:

The Stock setting as a baseline.

We all fell in love with this car on our test drives from the

dealership. We were all greatly impressed at how well mannered and
easily controlled a car of this size and height was. After all, this is
really the first production street performance SUV. err.. SAV. It
handled just like a car. Nothing at all reminded us of a truck like all
its competitors did.

We could really leave the car at 100% stock and fiddle with the

alignment to make feel better. In fact, I was sure I could resolve the
floaty feeling my wife was experiencing with a proper alignment. We had
the dealer check the alignment and it was all in "spec". I wasn't
surprised. From the experience of my professional motorsports friends,
I know that just because the factory published the spec, it didn't mean
that is what works best on the car. In fact, most high performance cars
out there have a horrible spec (Porsche GT3, GT2, Corvette Z06's, BMW
M3, etc) Many owners have deviated from the factory spec and been much
happier since.

Since my car was in "spec", that's how we decided to test it.

Toe alignment was very interesting. Yet it was "in spec". This

confirmed my thoughts on the floaty feeling coming from a "weird"
alignment. It was not even side to side. But yet the car tracked very
straight and exhibited correct turn in and turn radius. So off the the
proving grounds I went in the middle of the night. Below you will find
the data I collected.

Examination of the strut tower mount shows that the piston rod/nut

of the strut is pretty much dead center in the 3" hole on top of the
strut tower.

<TABLE width="100%" border=1>

<TBODY><TR><TD align=middle colSpan=5>Stock Settings - Baseline Measurements</TD></TR>

<TR>

<TD vAlign=center noWrap align=middle rowSpan=6>http://www.xoutpost.com/images/articl...tockcamber.jpg http://www.xoutpost.com/images/articl...ktireprint.jpg</TD>
<TD>Left Front Camber</TD>
<TD>-2.00 degrees</TD>
<TD>Right Front Camber</TD>
<TD>-2.01 degrees</TD>

</TR>
<TR>

<TD>Left Rear Camber</TD>
<TD>-4.03 degrees</TD>
<TD>Right Rear Camber</TD>
<TD>-4.00 degrees</TD>

</TR>
<TR><TD colSpan=5></TD></TR>
<TR><TD colSpan=2>Static Front Ride Height:</TD><TD colSpan=2>17.968"</TD></TR>
<TR><TD colSpan=2>Static Rear Ride Height:</TD><TD colSpan=2>18.15625"</TD></TR>
<TR><TD align=middle colSpan=5>Stock Settings - Performance Runs</TD></TR>
<TR><TD colSpan=3>Acceleration Run 1</TD><TD colSpan=2>60 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 2</TD><TD colSpan=2>61 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 3</TD><TD colSpan=2>60 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 4</TD><TD colSpan=2>58 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 5</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Average</TD><TD colSpan=2>59.6 mph avg </TD></TR>
<TR><TD colSpan=5></TD></TR>
<TR><TD colSpan=3>Autocross Run 1</TD><TD colSpan=2>148 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 2</TD><TD colSpan=2>152 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 3</TD><TD colSpan=2>147 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 4</TD><TD colSpan=2>146 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 5</TD><TD colSpan=2>147 secs</TD></TR>
<TR><TD colSpan=3>Autocross Average</TD><TD colSpan=2>148 secs avg</TD></TR>

</TBODY>

</TABLE>

At -2.0 degree of camber, the front tire contact patch still is

pretty oval and flat looking. This would mean that it still has
excellent grip.

I have no way of plotting the actual stopping points in this

article. I used cones to mark where the car had stopped and marked the
floor with chalk as I moved the cones per test session. The cones
spread was about 5 foot of difference from the two extremes. I couldn't
take a picture of the area where I had the cones as I didn't want to
attract the attention of the security guards patrolling the area with a
flash. Each section below will have comments on what the observed
changes were.

The Free Camber Setting

This is probably the most popular suspension modification in the BMW

enthusiast community as it is easily performed and 100% free. All that
is required is to remove the alignment pin, loosen the 3 strut nuts and
slide the strut all the way in and then tighten the strut nuts.
Instructions to this can be found here (--->insert link<---)

With the large difference in camber that the X5 has front to rear,

any bit will help with getting the car to become closer to neutral. I'm
sure lessening the rear camber and performing the Free Camber setting
will have an impact that you can feel right away. However, I've put
constraints on changing anything in the rear so I can measure what the
changes in the front were doing.

15 minutes of adjustment to add the Free Camber setting and I was

ready to drive off to the proving grounds again. Once the alignment pin
was removed, the strut hat was slide about 1/8" inwards, max. The
results are below:

<TABLE width="100%" border=1>

<TBODY><TR><TD align=middle colSpan=5>Free Camber Settings</TD></TR>

<TR>

<TD vAlign=center noWrap align=middle rowSpan=6>http://www.xoutpost.com/images/articl...freecamber.jpg http://www.xoutpost.com/images/articl...rtireprint.jpg</TD>
<TD>Left Front Camber</TD>
<TD>-2.30 degrees</TD>
<TD>Right Front Camber</TD>
<TD>-2.30 degrees</TD>

</TR>
<TR>

<TD>Left Rear Camber</TD>
<TD>-4.03 degrees *</TD>
<TD>Right Rear Camber</TD>
<TD>-4.00 degrees *</TD>

</TR>
<TR><TD colSpan=5></TD></TR>
<TR><TD colSpan=2>Static Front Ride Height:</TD><TD colSpan=2>17.9055"</TD></TR>
<TR><TD colSpan=2>Static Rear Ride Height:</TD><TD colSpan=2>18.15625"</TD></TR>
<TR><TD align=middle colSpan=5>Free Camber Settings - Performance Runs</TD></TR>
<TR><TD colSpan=3>Acceleration Run 1</TD><TD colSpan=2>60 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 2</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 3</TD><TD colSpan=2>60 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 4</TD><TD colSpan=2>60 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 5</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Average</TD><TD colSpan=2>59.6 mph avg </TD></TR>
<TR><TD colSpan=5></TD></TR>
<TR><TD colSpan=3>Autocross Run 1</TD><TD colSpan=2>147 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 2</TD><TD colSpan=2>146 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 3</TD><TD colSpan=2>145 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 4</TD><TD colSpan=2>147 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 5</TD><TD colSpan=2>146 secs</TD></TR>
<TR><TD colSpan=3>Autocross Average</TD><TD colSpan=2>146.2 secs avg</TD></TR>

</TBODY>

</TABLE>

* - Note that we left the rear camber alone to isolate only the changes in the front camber.

At -2.3 we start to see the contact patch taper off on the outside

and load a little more on the inside. I was surprised to see how
quickly we could observe the change.

When I overlapped the 5 stock braking points to these 5 braking

points, they were pretty much in the same 5 foot range with the except
that 2 were out further by 6 inches and 8 inches.

Rogue Engineering Camber Plates setting

There are only 3 ways that I know of to get more camber then what

the factory design allows for: Lower the car, make the mounting slots
longer, or changing the strut hats to camber plates. Each has its own
sets of pros and cons. The elongation of mounting slots is often the
worst choice to do as it weakens the strut tower unless properly
reinforced, which means you are gonna pay big bucks so you should have
done camber plates in the first place.

When I first received the plates, I was surprised they were not a

full top hat replacement. Instead they are add-on spacer plates that
change the stud mount locations. I asked Ben about this design. Ben had
pointed out at the plates were have been cost prohibitive to produce as
a one piece unit and would require a new bushing to mount the strut. A
high performance bearing like a monoball (used in race cars) would not
last for street duty and requires to be replaced too often. In Ben's
own words "The
biggest issue with factory mounts is that they are great for 99% of all
BMW owners/leasees, since they won't modify the car at all. For those
looking to "tweak" BMWs already superlative engineering, there are
products such as these plates which make it possible. Not trying to
redesign the mount, just improve it a little."

Ben also explained that the plates are aircraft grade aluminum and
anodize to protect it against the elements. the studs used to mount are
rated at 10.9 hardness, the same as the factory studs.

Since there is no shear forces at the strut mount, this design is

absolutely safe. The bushing allows for movement of the strut already.
Keep in mind, the factory strut nuts are only tightened down to 18
ft-lbs. That's pretty much the same as hand-tight.

This is the same design as the Dinan camber plates. In fact, they are very similar in every dimension.

<CENTER>

<TABLE>

<TBODY><TR><TD align=middle colSpan=3>Rogue Engineering Camber Plates</TD></TR>

<TR>

<TD>http://www.xoutpost.com/images/articles/252/3.jpg</TD>
<TD>http://www.xoutpost.com/images/articles/252/4.jpg</TD>
<TD>http://www.xoutpost.com/images/articles/252/32.jpg</TD>

</TR>

</TBODY>

</TABLE>
</CENTER>

The installation on this very straight forward but does require a

fresh alignment as the front will increase in toe out beyond factory
specs. After our installation, we aligned the car. However, we took the
opportunity to correct the front toe this time and made them not only
even, but set it so that under rolling resistance, we had zero toe for
a faster response in turn in. You can find the installation
instructions here.

I wasn't able to test immediately as it was rather difficult to get the
keys back from my wife. But eventually I was able to do another
midnight madness run at the proving grounds. The results are below:

<TABLE width="100%" border=1>

<TBODY><TR><TD align=middle colSpan=5>Rogue Camber Plate Settings</TD></TR>

<TR>

<TD vAlign=center noWrap align=middle rowSpan=6>http://www.xoutpost.com/images/articles/252/rogue.jpg http://www.xoutpost.com/images/articl...etireprint.jpg</TD>
<TD>Left Front Camber</TD>
<TD>-2.50 degrees minimum to -2.8 degrees maximum *</TD>
<TD>Right Front Camber</TD>
<TD>-2.50 degrees minimum to -2.8 degrees maximum *</TD>

</TR>
<TR>

<TD>Left Rear Camber</TD>
<TD>-4.03 degrees **</TD>
<TD>Right Rear Camber</TD>
<TD>-4.00 degrees **</TD>

</TR>
<TR><TD colSpan=5></TD></TR>
<TR><TD colSpan=2>Static Front Ride Height:</TD><TD colSpan=2>17.968</TD></TR>
<TR><TD colSpan=2>Static Rear Ride Height:</TD><TD colSpan=2>18.15625"</TD></TR>
<TR><TD align=middle colSpan=5>Free Camber Settings - Performance Runs</TD></TR>
<TR><TD colSpan=3>Acceleration Run 1</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 2</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 3</TD><TD colSpan=2>60 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 4</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Run 5</TD><TD colSpan=2>59 mph</TD></TR>
<TR><TD colSpan=3>Acceleration Average</TD><TD colSpan=2>59.2 mph avg </TD></TR>
<TR><TD colSpan=5></TD></TR>
<TR><TD colSpan=3>Autocross Run 1</TD><TD colSpan=2>146 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 2</TD><TD colSpan=2>144 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 3</TD><TD colSpan=2>146 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 4</TD><TD colSpan=2>144 secs</TD></TR>
<TR><TD colSpan=3>Autocross Run 5</TD><TD colSpan=2>145 secs</TD></TR>
<TR><TD colSpan=3>Autocross Average</TD><TD colSpan=2>145.0 secs avg</TD></TR>

</TBODY>

</TABLE>

* - With the Rogue Plates in, we still had the adjustment option of

sliding the studs in the slotted holes. The measurements above are the
2 extreme ranges. We opted to go with the maximum negative camber to
closely match the rear as much as possible.

** - Again, we opted not to change the rear camber settings to isolate only the changes in the front.

At -2.8 degrees we are seeing the contact patch definitely morph into a
tear drop shape. Technically this would have less grip on a straight
flat surface then the stock setting but would flaten out as we cornered
giving us a little more lateral loading.

The Rogue Engineering plates positioned the strut piston/nut almost

1" inward from its original position, the center of the hole on top of
the strut tower. This changed the Steering Axis Inclination, resultant
Included Angle and the scrub radii significantly. However, the changes
were uniform from side to side. When I let go of the steering wheel
after I turned, the steering wheel did return to center by itself like
normal. I couldn't tell a difference in how long it took to self
center.

Braking is finally observed to require a little further distance.

The 5 cones that marked the braking points with the Rogue Camber plates
started at the middle of the stock and ended 3 feet from the maximum
distance on the stock setting.

The wife's impression:

After the installation of the Rogue Camber plates, we gave the car

a fresh alignment. My wife then drove the car the rest of the week as
normal.

After her first day with the car, her first comment to me was "Either I'm really tired from the test, or the car drove itself home."

I left that comment alone.

A few days later, she accused me with: "You did something to the car didn't you?!?!?"

To which I replied: "What do you mean, Dear?"

Then she beamed as she said "The car handles beautifully!!! Its no longer floaty nor feel like crap anymore!" Then I told her "Yah, we just put some camber plates on the front and gave it a fresh alignment."

Her final comment was "Its like a night and day difference.
Before the car was very floaty above 70mph. Steering was very light and
barely any feedback. Now, it feels like it carrrrves into turns. I'm driving like a mad woman now!

To my wife's credit, she does have high performance driving

experience and can truly appreciate a well sorted car. As soon as she
is done with med school, we do plan on completing her training in my
Porsche 996 cup prepared race car.

Summary

<CENTER>

<TABLE>

<TBODY><TR>

<TD align=middle colSpan=3>The Results

</TD>

</TR>

<TR>

<TD vAlign=center align=middle width="33%">Stock Camber</TD>
<TD vAlign=center align=middle width="33%">Free Camber Adjustment</TD>
<TD vAlign=center align=middle width="33%">Rogue Camber Plates
at max negative camber
</TD>

</TR>
<TR>

<TD align=middle>http://www.xoutpost.com/images/articl...tockcamber.jpg</TD>
<TD align=middle>http://www.xoutpost.com/images/articl...freecamber.jpg</TD>
<TD align=middle>http://www.xoutpost.com/images/articles/252/rogue.jpg</TD>

</TR>
<TR>

<TD align=middle>Camber: -2.0 fixed.</TD>
<TD align=middle>Camber: -1.9 to -2.3</TD>
<TD align=middle>Camber: -2.5 to -2.8</TD>

</TR>

</TBODY>

</TABLE>
</CENTER>

Out of options that we tested, the Rogue Engineering camber plate

definitely had the greatest impact on improving the overall handling
and feeling of the car. The camber more closely matches that of the
rear giving the car a much better balance while cornering and
maintaining a little understeering characteristic to keep the car very
well mannered and safe. Perfectly safe for beginner drivers as well as
experienced road race drivers.

My impressions were that turn in was the sharpest with the camber

plates. Feed back was immediate and accurate through the steering
wheel. The car had lost all signs of floatiness and was extremely
stable at all speeds I tested at in straight line acceleration and
braking, cornering and braking while cornering.

If you noticed in the data collections, the ride height remained the
same with the Rogue Engineering camber plates and the stock setting.
When the strut angle was moved inward, I expected that the car would be
lowered somewhat, after all, the weight is the same but there is
increased angle. However, the thickness of the spacer fills the gap
difference and raises the car back to normal height preserving much of
the car's original engineering specs (dive/anti dive, squat/anti squat,
brake bias, etc) With the free camber adjustment, I measured a 1/16th
inch drop in ride height. Not much at all really, since there really
isn't much movement of the top mounting point.

The changes in Steering Axis Inclination (SAI) where consistent on

both sides which resulted in identical scrub radii. The included angle
remained less the SAI, as with stock specs. What this basically means
is that the car is set to track straight and the steering wheel still
returns to center after a turn when you let it go.

Through my primitive performance tests, I could not find any

significant difference in contact patch effectiveness and but was able
to gain handling confidence; more with each level of modification.

Both the Rogue Engineering camber plates and the free camber

adjustment with proper alignment will be a change that you can feel.
Obviously the camber plates will have a greater impact. Are these
plates a world of difference? Probably not, but they do bring a new
level to accuracy in the handling of your X5 and make it more
enjoyable. I truly believe that the combination of added camber and a
correct alignment is what contributed to why my wife loves the handling
of her X5 so much.

Did the plates really add significant handling performance? I don't

know for sure. As you can see, the acceleration and deceleration runs
were pretty much the same all around. You have to factor in some time
for driver error, reaction, different daily conditions, etc. Its also
highly possible that the drop in my autocross times were due to having
more runs/practice with the course. Without proper data acquisition and
a controlled environment to re-run the test, we don't have factual data
representation of the changes. What we do know is that the data we
collected strongly suggests that there is a great improvement in
handling. We know that we feel much more confident with the setup and
that the car does take a more neutral balance going through corners at
speed where it normally exhibited understeer behavior.

Since I didn't buy a set of the Dinan camber plates, there's not much I
can say about it, but do expect it to have a similar effect on handling
and road feel as the Rogue Engineering ones, albeit it at a higher
price tag.

My wife is extremely happy with the camber plates that we installed.

I asked her, if she test drove an X5 that had the plates and compared
it to her car when it didn't have the plates, yet it was in spec
alignment form, would that test drive be enough to persuade her to
spend the money for the camber plates? Her answer is a definite yes.
And this is coming from someone who is adamant about not spending money
on performance for a street only vehicle and was perfectly happy with
the handling in her previous X5 3.0i. I then qualified the question
again to her by comparing the camber plate equipped X5 to her perfectly
handling X5 3.0i, which car would she choose? She just smiled and said "You wouldn't get your lovely wife an X5 without the camber plates would you?" See boys, THIS is the perfect example of "it's better to beg for forgiveness then to ask for permission" =)

For more details and purchasing information, please visit Rogue Engineering.

At minimum, I would suggest people who feel dull turn in, annoyed by
the factory set understeer limits, or a vagueness in steering feel, to
get a proper alignment from a qualified shop. Even better, would be to
give yourself the free camber adjustment and an alignment. And the best
option would be to get these camber plates installed and an alignment.

References:
Free Negative Camber for the E53 BMW X5

Rogue Engineering Camber Plates for the BMW E53 X5