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[roy@gambitmotorsport]

I have an '07 E92 335i coupe with sport package and standard "real" steering package. After about 10K miles and an auto-x, my RFTs were worn down to nothing on the front outside edges, so I went in for some new tires and an alignment.

For tires, I picked the Continental ContiSportContact 3's, for many reasons, some of which include lightest-in-class and use by the BMW driving school. Rating this is a different story for a different day, after I get several Angeles Crest runs and auto-x's in. Visually, I was surprised by the huge treadline gaps (although the rest of the tread is virtually solid strips). Ridewise, through town, I had forgotten that a sports car doesn't have to jolt back to you inconsequential bumps, like the RFTs did.

Anyway, on to my E92 Alignment Story - I'm pretty sure new tires don't alter your alignment; in fact, they don't really, all measurements are at the rims, so the numbers I'm about to post are what a 335i with 10K miles on it has for suspension settings in at least my case:

Wheel Before After Spec

Camber
F_Left -0.5, -0.5, -0.8 to 0.2
F_Right 0.1, -0.3, -0.8 to 0.2
R_Left -1.6, -1.8, -2.1 to -1.6
R_Right -1.4, -1.8, -2.1 to -1.6

Toe
F_Left 0.04, 0.12, 0.03 to 0.20
F_Right 0.20, 0.12, 0.03 to 0.20
R_Left 0.14, 0.15, 0.10 to 0.20
R_Right -0.09, 0.16, 0.10 to 0.20

The "Before" is what my car was and the "After" is what JC Autohouse in Temple City was able to adjust it to with a 4-wheel computer alignment. BTW, fixing the camber on the front right wheel took knocking off a nipple on the top of the shock mount, otherwise, it was already at its best (bad) setting.

I did not do an "in car sitting" during this alignment. If skipping that was foolish based on experience, let me know.

I'm interested in what folks with experience in suspension settings think of my "stock" numbers (Cyrus at JC Autohouse told me most new cars are like this) and what amount of difference might be felt, road and track, with the new settings. Also, any recommendation on changes. Cyrus hadn't really worked on this car much before and is happy to have me come back in to make adjustments. BTW, his equipment is all Hunter and he spent about an hour making the adjustments. The front is not too adjustable, but the rear sounds like another story.

One thing I would say is noticeably different, is that the car rolls much easier now. Moving up at stop signs with cars in front and traversing the car port takes more braking, rather than just letting the car settle to a stop. I'm pretty sure it's not just in my head and I don't see where the tires would make much of a difference (my old RFTs were left pumped pretty high for the LA BMW auto-x, prior to replacement).


Thanks,
Roy

[Orb]

Originally Posted by roy@gambitmotorsport

I have an '07 E92 335i coupe with sport package and standard "real" steering package. After about 10K miles and an auto-x, my RFTs were worn down to nothing on the front outside edges, so I went in for some new tires and an alignment.

For tires, I picked the Continental ContiSportContact 3's, for many reasons, some of which include lightest-in-class and use by the BMW driving school. Rating this is a different story for a different day, after I get several Angeles Crest runs and auto-x's in. Visually, I was surprised by the huge treadline gaps (although the rest of the tread is virtually solid strips). Ridewise, through town, I had forgotten that a sports car doesn't have to jolt back to you inconsequential bumps, like the RFTs did.

Anyway, on to my E92 Alignment Story - I'm pretty sure new tires don't alter your alignment; in fact, they don't really, all measurements are at the rims, so the numbers I'm about to post are what a 335i with 10K miles on it has for suspension settings in at least my case:

Wheel Before After Spec

Camber
F_Left -0.5, -0.5, -0.8 to 0.2
F_Right 0.1, -0.3, -0.8 to 0.2
R_Left -1.6, -1.8, -2.1 to -1.6
R_Right -1.4, -1.8, -2.1 to -1.6

Toe
F_Left 0.04, 0.12, 0.03 to 0.20
F_Right 0.20, 0.12, 0.03 to 0.20
R_Left 0.14, 0.15, 0.10 to 0.20
R_Right -0.09, 0.16, 0.10 to 0.20

The "Before" is what my car was and the "After" is what JC Autohouse in Temple City was able to adjust it to with a 4-wheel computer alignment. BTW, fixing the camber on the front right wheel took knocking off a nipple on the top of the shock mount, otherwise, it was already at its best (bad) setting.

I did not do an "in car sitting" during this alignment. If skipping that was foolish based on experience, let me know.

I'm interested in what folks with experience in suspension settings think of my "stock" numbers (Cyrus at JC Autohouse told me most new cars are like this) and what amount of difference might be felt, road and track, with the new settings. Also, any recommendation on changes. Cyrus hadn't really worked on this car much before and is happy to have me come back in to make adjustments. BTW, his equipment is all Hunter and he spent about an hour making the adjustments. The front is not too adjustable, but the rear sounds like another story.

One thing I would say is noticeably different, is that the car rolls much easier now. Moving up at stop signs with cars in front and traversing the car port takes more braking, rather than just letting the car settle to a stop. I'm pretty sure it's not just in my head and I don't see where the tires would make much of a difference (my old RFTs were left pumped pretty high for the LA BMW auto-x, prior to replacement).


Thanks,
Roy

I had two alignments by hunter alignment system that were not KDS and in both cases the alignment was out by a miles. I ended up getting them fixed with in one day in both cases at the dealer. I’m not sure about the specific with KDS system but it makes a difference.

You missing caster, thrust angle and steer ahead in you alignment. If you did not get a thrust angle reading this the alignment will not be correct. Car is supper sensitive to this.

The rest of your alignment looks fine and I would keep to the mid point on all toes setting. The front camber should be set to a -0.5 to -0.6.

When you knock off the nipples on the top hats of the struts then you will over -0.5 degrees front camber so something is a bit off?

I would increase your tire pressure up 2-3 PSI more than used on RFT. Almost everyone does this when the dump the RFT. I run 36.5 on the front and 39.5 fro the rear on 19” which is fine but 18” it should be 3 PSI more both front and rear. You will notice this right away.

Orb

[roy@gambitmotorsport]

Originally Posted by Orb

I had two alignments by hunter alignment system that were not KDS and in both cases the alignment was out by a miles. I ended up getting them fixed with in one day in both cases at the dealer. I’m not sure about the specific with KDS system but it makes a difference.

You missing caster, thrust angle and steer ahead in you alignment. If you did not get a thrust angle reading this the alignment will not be correct. Car is supper sensitive to this.

The rest of your alignment looks fine and I would keep to the mid point on all toes setting. The front camber should be set to a -0.5 to -0.6.

When you knock off the nipples on the top hats of the struts then you will over -0.5 degrees front camber so something is a bit off?

I would increase your tire pressure up 2-3 PSI more thanfron used on RFT. Almost everyone does this when the dump the RFT. I run 36.5 on the front and 39.5 fro the rear on 19” which is fine but 18” it should be 3 PSI more both front and rear. You will notice this right away.

Orb

Thanks for the feedback.

Caster was measured and fell right in the middle of spec in all cases. I'm pretty sure he took thrust angle into account, since all the posters in his shop made reference to it, but I don't have my sheet with me. I just listed the things that changed, in my original post.

He had to knock the shock tower nipple off the front right in order to bring the camber any further negative than .01. Even with it off, max was -0.3.

I'm not sure what steer ahead is - could you explain? It's not when you adjust the front alignment to compensate for non-adjustable problems in the rear alignment, is it?

I may go back there for some adjustments and will ask about the difference with the KDS equipment.

I kept my 18" rims - so around 39.5 front and 42.5 rear would be ideal pressures? I love the new tires so far as acceleration traction, so far - much harder to break away in first and second!


Thanks!

[Randy@UED]

I had a similar experience and had to go back twice before they could get it perfect

[BMW MotorSport]

very good alignment info here.

[Orb]

Originally Posted by roy@gambitmotorsport

Thanks for the feedback.

Caster was measured and fell right in the middle of spec in all cases. I'm pretty sure he took thrust angle into account, since all the posters in his shop made reference to it, but I don't have my sheet with me. I just listed the things that changed, in my original post.

He had to knock the shock tower nipple off the front right in order to bring the camber any further negative than .01. Even with it off, max was -0.3.

I'm not sure what steer ahead is - could you explain? It's not when you adjust the front alignment to compensate for non-adjustable problems in the rear alignment, is it?

I may go back there for some adjustments and will ask about the difference with the KDS equipment.

I kept my 18" rims - so around 39.5 front and 42.5 rear would be ideal pressures? I love the new tires so far as acceleration traction, so far - much harder to break away in first and second!


Thanks!

There are a few things I can add to your first comments. There front camber and caster setting are really limited so it hard to screw them up. If your feeling the car is rolling more then I suggest you put in more caster. I like 7.5 degrees but the range is good for +/- 4 degrees from 7.2 degrees. Don’t over do it here but unless you have an H&R rear sway bar and you like heavier steering. I’ve tired 7.2 degrees and didn’t like it at all! I would suggest your try 7.3 to 7.5 degrees if all else fails. Also note when you try to maximize the front negitive camber the caster tends to be less as well.

Your tire pressure are fairly high and although there advantages under track condition you might find that under normal street driving that you have odd behaviors as you mentioned since your not loading the tire the same way. Tire pressure is very subjective and no two tire manufacture tires will perform the same way. Before you do anything else I would suggest you start at a balanced tire pressure setting of 35 PSI for the front and 39 PSI in the rear and go from there.

The one thing I did find out about he KDS system is they do preload the suspension for accuracy. This preloading certainly would help taking out slop for bushing and the strut top hats.

BTW, you comments about it being much harder to break away with higher tire pressures are true on flat surfaces with good traction. The opposite is true from bumpy surfaces with poor traction as you lose compliance in the tire.

Orb