Alignment Issue

[FrenchBoy]

Guys, I am happy to report that I think my alignment issue is fixed. I went back to the good people at Group2 tonight and the tech had me sit in the car and center the steering wheel while he redid the alignment. From the little post alignment test drive, it seems to be back to its normal state of perfection.

I am relieved! Especially since I am taking my baby to the track on Friday.

Here are the final alignment specs, which seem to work:
Front (L / R)
Camber: -1.13 / -1.19 deg
Caster: 6.86 / 7.10 deg
Toe: 0.04 in / 0.04 in

Rear (L / R)
Camber: -1.64 / -1.66 deg
Toe: 0.10 in / 0.05 in

[dawgdog]

Great new! See you tomorrow.

[rbk1115]

Glad to hear it is fixed!

[lucid]

Originally Posted by FrenchBoy

Guys, I am happy to report that I think my alignment issue is fixed. I went back to the good people at Group2 tonight and the tech had me sit in the car and center the steering wheel while he redid the alignment. From the little post alignment test drive, it seems to be back to its normal state of perfection.

I am relieved! Especially since I am taking my baby to the track on Friday.

Here are the final alignment specs, which seem to work:
Front (L / R)
Camber: -1.13 / -1.19 deg
Caster: 6.86 / 7.10 deg
Toe: 0.04 in / 0.04 in

Rear (L / R)
Camber: -1.64 / -1.66 deg
Toe: 0.10 in / 0.05 in

So, they did your previous alignment without centering the wheel?

Anyway, good to hear it is fixed.

[BMWM.D.]

While I am glad to hear that you got the problem resolved, I can see a few things that might have caused the issue. Hopefully, this will prove useful to some of you guys who need alignments in the future.

Let me start by first saying that no E9x M3 has active steering. It is even a fairly rare option on regular 3 series. There should be no additional charge for aligning an M3.

First, all BMWs are supposed to be heavily weighted during an alignment procedure. It is supposed to be 150 lbs. in each front seat, 150 lbs. in the back seat and I believe 60 lbs. in the trunk. If the car was not weighed down, the settings will not be correct when the car is going down the road at speed.

Next, there is the fact that a car will always want to pull to the side with the most positive camber setting. From your first alignment spec sheet, the right side has more positive camber than the left (L -1.14 R -1.02 ). Most alignment machines read in degrees and minutes (ie. 60 minutes in a degree) , so your front camber setting was a quarter degree more positive on the right which could cause a slight pull/drift that direction.

Also, if the car was not weighted properly during the first alignment, it is likely that when you sit in the car the left front drops a bit and the negative camber increases even more (than what you see on the 1st printout), which would increase the cross-camber and make the pull situation even worse.

Pulls or drifts can also be caused by uneven tire wear, but it is usually a result of poor cross-caster or cross-camber. Toe will not cause a pull, but it can cause stability issues.

If the rear toe is off, it can cause a thrust angle problem which leads to "dog tracking". The front and rear axles are supposed to be parallel to each other and perpendicular to the vehicle centerline. If the toe is off on one of the rear wheels, the thrustline changes. Toe will always want to equalize itself when driving, so guess what happens when the rear axle is no longer aligned with the front properly? The car drives sideways down the road and the result will be a crooked steering wheel and excessive tire wear.

Make sense?

[BMWM.D.]

Originally Posted by lucid

I don't know what the alignment specs for regular 3-series cars are, but can you even get more than -1 camber up front on a regular 3 series car even if you tried? Anyway, the M3 specs are stickied in this this section, so I assume you compared what you got to those? There might be some several sensors that regulate power steering assist, but I don't know the specifics.

Just so everyone knows, I looked up the alignment specs for a sport package E90 (non-M) and they are different than the specs for the M3. Here they are:

E9x sport package

front camber: -33'
front toe: 14'

rear camber: -1 50'
rear toe: 18'


E9x M3

front camber: -1 10'
front toe: 10'

rear camber: - 1 45'
rear toe: 10'

Everything is different, but the biggest difference is the front camber. So for future reference, make sure whoever does your alignment uses the correct alignment data.

[lucid]

Thanks for the regular E90 vs M3 alignment spec comparison and the other info.

Originally Posted by BMWM.D.

Next, there is the fact that a car will always want to pull to the side with the most positive camber setting. From your first alignment spec sheet, the right side has more positive camber than the left (L -1.14 R -1.02 ). Most alignment machines read in degrees and minutes (ie. 60 minutes in a degree) , so your front camber setting was a quarter degree more positive on the right which could cause a slight pull/drift that direction.

His camber specs seem to be already reported in degrees, so I am not sure why you are applying a minutes to degrees conversion here?

[BMWM.D.]

Originally Posted by lucid

Thanks for the regular E90 vs M3 alignment spec comparison and the other info.



His camber specs seem to be already reported in degrees, so I am not sure why you are applying a minutes to degrees conversion here?

Because what he posted was very likely in the minute/degree format and he was not aware of it. I guess I was just trying to clarify that - 1.14 degrees is actually -1 degree and 14 minutes or 14/60th of a degree (not 14/100th of a degree). Makes a difference when really trying to dial in an alignment.

[lucid]

Originally Posted by BMWM.D.

Because what he posted was very likely in the minute/degree format and he was not aware of it. I guess I was just trying to clarify that - 1.14 degrees is actually -1 degree and 14 minutes or 14/60th of a degree (not 14/100th of a degree). Makes a difference when really trying to dial in an alignment.

Hmmm. I see a decimal point there. When I look at my specs, I see the decimal points, so I must assume they are in degrees. Well, actually, my tech told me they were reported in degrees when we were discussin them. If they were in minutes, the computer should have reported them in the appropiate format. The minute mark is a ', which is not hard to represent. Anyway, I haven't used any of these machines personally, so maybe you know something about how these machines report specs that I don't...

[BMWM.D.]

Originally Posted by lucid

Hmmm. I see a decimal point there. When I look at my specs, I see the decimal points, so I must assume they are in degrees. Well, actually, my tech told me they were reported in degrees when we were discussin them. If they were in minutes, the computer should have reported them in the appropiate format. The minute mark is a ', which is not hard to represent. Anyway, I haven't used any of these machines personally, so maybe you know something about how these machines report specs that I don't...

I don't know, it is possible his printout was formated in 100's of a degree but without an actual scan on the printout it is hard to say. All I saw above was just what he read off the sheet and typed into the computer.

I have a couple of my alignment sheets in front of me from when I dialed in my '67 for reference. While I don't think I can duplicate the format they are in on my home computer (no "degree" symbol), I will substitute the * instead just to show you how our machine reads.

My front camber was: -1*02' and -0*57' (L & R)

So you see, it is still in the degree format but is using a 1/60 scale for the parts of a degree rather than 1/100. It was kinda strange when I first started aligning cars like that, but now it is second nature. If the shop he used does not specialize in European cars, it could be in the 100th of a degree format.

[BMWM.D.]

Originally Posted by lucid

Hmmm. I see a decimal point there. When I look at my specs, I see the decimal points, so I must assume they are in degrees. Well, actually, my tech told me they were reported in degrees when we were discussin them. If they were in minutes, the computer should have reported them in the appropiate format. The minute mark is a ', which is not hard to represent. Anyway, I haven't used any of these machines personally, so maybe you know something about how these machines report specs that I don't...

I have a couple of my alignment sheets in front of me from when I dialed in my '67 for reference. While I don't think I can duplicate the format they are in on my home computer (no "degree" symbol), I will substitute the * instead just to show you how our machine reads.

My front camber was: -1*02' and -0*57' (L & R)

So you see, it is still in the degree format but is using a 1/60 scale for the parts of a degree rather than 1/100. It was kinda strange when I first started aligning cars like that, but now it is second nature. If the shop he used does not specialize in European cars, it could likely be in the 100th of a degree format.

Edit: I just noticed his caster was 6.86 which means it was not in the minute format. Car was probably at a general alignment shop, which expains that. I get stuck in my little BMW world sometimes

[dcstep]

Originally Posted by BMWM.D.

...

My front camber was: -1*02' and -0*57' (L & R)

...

That's degrees and minutes, which is pretty standard, particularly at BMW dealers. Just divide the 2d number by 60 to convert it to % or degrees. Hence, 57' is just short of 1-degree.

Dave

[FrenchBoy]

Sorry I did not respond sooner to this, I was away with the family.

As a follow-up, my alignment sheet lists all the angles and decimal places, i.e. -1.13 degrees. Not in degree/minutes.