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Problem with my alignment, maybe someone could help

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Old 04-15-2012 | 09:17 PM
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Problem with my alignment, maybe someone could help

Hi everyone,

Last month, I installed my new PSS9 coilovers. I left the alignment as is at that time. I adjusted my height at 13.5" at all corners. The car immediately start to handle better and I was very happy. I adjusted my shock "softness" to 5 in front and 6 in rear.

My tires are Michelin PS2 245/35/19 mounted on forged alloy wheels 19x8.5.

Last week, I went to the alignment shop to have a good alignment. Since that, the car handle like a crap. Everything seems to be "too smooth".

Here I post my new alignment setup in hope that someone could take a look at it:

Before (all in degrees):
Caster Front-Left: 7.27
Caster Front-Right: 7.32
Camber Front-Left: -1.40
Camber Front-Right: -1.59
Toe Front-Left: -0.30
Toe Front-Right: 0.11
Camber Rear-Left: -2.03
Camber Real-Right: -2.39
Toe Rear-Left: 0.22
Toe Rear-Right: 0.17

After:
Caster Front-Left: 7.74
Caster Front-Right: 7.95
Camber Front-Left: -1.33
Camber Front-Right: -1.30
Toe Front-Left: 0.17
Toe Front-Right: 0.17
Camber Rear-Left: -1.75
Camber Real-Right: -1.75
Toe Rear-Left: 0.03
Toe Rear-Right: 0.03

Is this something wrong with this alignment? I really hesitate to return to that shop again. I will probably try the dealer in the near future.
Old 04-15-2012 | 09:34 PM
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Did you have an alignment immediately after installing the coilovers? Your before alignment specs look within factory specs. There is also not a large difference between before and after.

What was your stock height before the coilovers?
Old 04-15-2012 | 10:44 PM
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Looks like they corrected the cross toe; that's good.

Too much negative camber in the rear, not enough negative camber in the front. This will give understeer at the limit though that's not necessarily bad on a non-tracked car.

Most people don't complain about handling being "too smooth." Can you be more specific?
Old 04-15-2012 | 10:49 PM
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The front cross toe just means the steering wheel wasn't straight. The camber change was also pretty small, I am surprised he noticed a large difference in handling between the two specs
Old 04-15-2012 | 11:17 PM
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Originally Posted by JCrane82
Did you have an alignment immediately after installing the coilovers?
I had my alignment done 3 weeks after I installed my coilovers.

Originally Posted by JCrane82
What was your stock height before the coilovers?
Before it was 14.5". I dropped about 1 inch.

Originally Posted by NotAPreppie
Most people don't complain about handling being "too smooth." Can you be more specific?
The steering feedback is not as good as before. It feel like the tire are underinflated but it is not the case.

Originally Posted by JCrane82
The front cross toe just means the steering wheel wasn't straight. The camber change was also pretty small, I am surprised he noticed a large difference in handling between the two specs
There is definitively a difference. Your comments encourages me. Maybe I just have to get used to the new settings. I do not push the car too much because I don't like the feeling.
Old 04-15-2012 | 11:38 PM
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The only difference you might notice is the rear toe is less....might make the rear feel a bit looser.

Other than that the rest isn't likely to noticeble...camber is a bit more rear biased than I like..I would increase the front a bit and decrease the rear ...maybe by .5 on both

I would also go with zero toe in the front..it will make turn in feel a bit crisper
Old 04-16-2012 | 12:22 AM
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This is a simple possibility - did you know what the tire pressures were before? exactly?

Until the guy doing my alignment told me, I didn't realize that checking and equalizing tire pressures all around was part of a good alignment. Seems obvious in retrospect, but i didn't realize it at first.

Maybe the "softness" has nothing to do with the suspension, and really was due to a change in tire pressures?
Old 04-16-2012 | 07:18 AM
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The after #s look good to me
Old 04-16-2012 | 08:48 AM
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Originally Posted by topolittle
I had my alignment done 3 weeks after I installed my coilovers.


Before it was 14.5". I dropped about 1 inch.


The steering feedback is not as good as before. It feel like the tire are underinflated but it is not the case.
Just so I understand correctly, you installed your coilovers about 4 weeks ago (which dropped ride height by about 1 inch), and had an alignment done about 1 week ago?

If this is true, I am very surprised that your before alignment specs looked as good as they did. A 1 inch drop in ride height will add negative camber and should change toe about 0.1-0.15 degrees

If you want more steering feedback, add toe out in the front.

After looking at your before numbers again, I may have the answer for your change in steering feel. The before front toe numbers were -0.30 and +0.11 (different because the steering wheel wasn't straight compared to the combined toe). This front toe is the same as having -0.19 on both wheels. Moving forward to the "after" settings, and front toe is +0.17. That is a large change in front toe. You went from 0.19 degrees toe out to 0.17 degrees toe in. That is why you "lost" your steering response.

My suggestion is to have it realigned with front toe at zero or up to -0.15, as more will increase tire wear. You have to remember that this is static toe measurements, and on a RWD car the toe out will increase as you increase drag (speed up).
Old 04-16-2012 | 07:07 PM
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Originally Posted by JCrane82
Just so I understand correctly, you installed your coilovers about 4 weeks ago (which dropped ride height by about 1 inch), and had an alignment done about 1 week ago?
Exactly!

Originally Posted by JCrane82
If this is true, I am very surprised that your before alignment specs looked as good as they did. A 1 inch drop in ride height will add negative camber and should change toe about 0.1-0.15 degrees
I don't know my alignment settings prior to the coilovers installation. But the numbers before and after alignment are accurate, I saw those myself.

If you want more steering feedback, add toe out in the front.

Originally Posted by JCrane82
After looking at your before numbers again, I may have the answer for your change in steering feel. The before front toe numbers were -0.30 and +0.11 (different because the steering wheel wasn't straight compared to the combined toe). This front toe is the same as having -0.19 on both wheels. Moving forward to the "after" settings, and front toe is +0.17. That is a large change in front toe. You went from 0.19 degrees toe out to 0.17 degrees toe in. That is why you "lost" your steering response.

My suggestion is to have it realigned with front toe at zero or up to -0.15, as more will increase tire wear. You have to remember that this is static toe measurements, and on a RWD car the toe out will increase as you increase drag (speed up).
Thank you for your suggestion, it is very helpful. After reading a lot on that topic it makes sense. At first, I asked the technician to have 0 toe in the front, but he refuse, telling me that this will not be "in the specs". I will return there and ask him again. What would be the best compromise between tire wear and steering feedback ? 0 toe or 0.05 toe out on each side ?
Old 04-16-2012 | 08:26 PM
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If they won't do what you want...you might as well find someplace that will

A lot of shops will only do "spec" alignments for liability reasons...so if you want something "out of spec" you will need to find a shop that will

I would try 0 toe first......
Old 04-16-2012 | 09:11 PM
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Originally Posted by topolittle
Exactly!


I don't know my alignment settings prior to the coilovers installation. But the numbers before and after alignment are accurate, I saw those myself.

Thank you for your suggestion, it is very helpful. After reading a lot on that topic it makes sense. At first, I asked the technician to have 0 toe in the front, but he refuse, telling me that this will not be "in the specs". I will return there and ask him again. What would be the best compromise between tire wear and steering feedback ? 0 toe or 0.05 toe out on each side ?
I have attached the factory specifications for the Series I Sport suspension (assuming you have the 6MT with sport suspension). The front toe is 11'+/-21', or 0.183 +/- 0.35 degrees.....making an in spec range of -0.166 to +0.533 (negative is toe out, positive is toe in). Your original toe measurement of -0.19 was out of factory spec, and therefore the tech wanted to adjust it. Technically a zero toe alignment would still be in spec, and the shop should have no issue meeting that request. I am with Dannobre, find another shop, or better yet.....learn how to align your car yourself. Performing your own alignments are pretty easy, and can be done with house hold tools.

As for what front toe setting is the best compromise between tire wear and steering feedback.....only you can answer that. Suspensions and alignments have no "best" setting; everything is a compromise. More toe out gives you more steering feedback, yet yields higher scrub on the tires resulting in increased tire wear. Only you can decide how much is right. There are a few threads out there where forum members provide their recommended alignment numbers. Take these suggestions with a grain of salt, because everyone has different opinions and applications. Each driver likes a different feel. Your current setup could be perfect for one person, but aweful for the next. Application also matters. I don't use the same alignment for autocross that I would use for a track day. To make things simple, I suggest that you adjust to zero toe and reevaluate. Remember, a zero static toe will result is a slight toe out angle under drag. This is why most manufactures suggest a slight toe in statically, to reduce tire wear since the dynamic toe will be closer to zero under drag.

I would provide my alignment specs, but I am currently setup for autocross and would not suggest these numbers for a regular daily driver (even though I daily drive mine). If you are really curious, let me know and I will share.
Attached Thumbnails Problem with my alignment, maybe someone could help-front-sport-susp.jpg  
Old 04-17-2012 | 07:12 AM
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Thank you for your offer, but as you said, it is very personal. I will try 0 toe first and see if I like.

Now I understand much better the alignment number, Thank you for everyone that answered that thread.
Old 04-28-2012 | 09:16 AM
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Hi everyone,

Just to give you a follow-up, I had the car realigned yesterday with those specs:
Front:
Caster: - 7.2 (both side)
Camber: -1.6 (both side)
Toe: -0.1 (total)

Rear:
Camber: -1.6 (both side)
Toe: 0.2 (total)

The change in the steering feedback is like day and night. I feel much better the car and I can start to really enjoy my new coillovers. I will check my tire wear frequently but I don't think that this will be a problem.
Old 04-28-2012 | 12:59 PM
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^^^^^great specs to start with. You will enjoy your "new" steering response. Keep us updated about any changes you make in the future.
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