Wheel Alignment Specs

[Loren]

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

- A caster adjustment is normally not necessary and is therefore not present! If required in a customer service matter, a caster adjuster may be installed (Serv. No. 40 19 23/Installing caster eccentrics).

- The toe-difference angle value is also influenced by the vehicle height! For this reason the measured result must be evaluated accordingly! No action is necessary in the case of small deviations from the toe-difference angle required value, as long as the value to the right and the left is almost the same.

Edited November 25, 2008 by Loren
Updated images (specs did not change)

[KevinC]

Yuk!

I would never get my car aligned based on these factory specs. These are much sloppier than anything my alignment shop would ever do. These specs are better than the factory Boxster specs I have seen posted, but they still allow 1/3 degree difference in camber on each axle, and allow positive camber on the front axle. Not good.

[NeverFastEnough]

Loren,

Do the X74 specs apply to the X73 suspension?

I just added the X73 suspension to my C4S but unfortunately with the aerokit it is "too low" to be aligned by the laser guided alignment devices (at my Porsche dealer) :( so I have to find someplace else (with the old mechanical alignment) to set the car up properly.

Thanks in advance.

[Loren]

Loren,

Do the X74 specs apply to the X73 suspension?

I just added the X73 suspension to my C4S but unfortunately with the aerokit it is "too low" to be aligned by the laser guided alignment devices (at my Porsche dealer) :(  so I have to find someplace else (with the old mechanical alignment) to set the car up properly.

Thanks in advance.

X74 is somewhat different that the TT/C4S X73. But if your X73 kit lowered your car 30 mm then it should be fairly close. Anytime you change the ride height you are altering the wheel alignment so it needs to be done. Also, on 4WD cars the steering angle sensor needs to be re-calibrated for the lowered car - this must be done with a PST2.

X73 alignment is likely in a service manual supplement I have on order. Sometimes they take a week to get and sometimes they take 3 months! As soon as I have somthing newer I will post it here.

Here is all I have for C4S at this point:

[NeverFastEnough]

Thanks Loren!

The car seems to track OK for now. There does seem to be a fair amount of range in the alignment specs for the C4S you posted...they almost overlap. Despite my dealer's advice of only "watching out for uneven tire wear" I would still like to get the car set up correctly.

I wonder if they set up the steering angle sensor with the PST2 <_< .

Once again thanks for the info. It will be interesting to see what the supplement recommends.

[Loren]

Updated C4S alignment and height values:

Height -- The 911 Carrera 4S, up to model year 2004, is delivered with just one running gear tuning. As of model year 2004, the X73 running gear (20 mm lower) is available as an option.

Alignment:

[NeverFastEnough]

Loren,

Thanks for the info.

[dammad]

Quick follow up question.

Loren's alignment numbers at the beginning of the thread seem to indicate only one alignment for a standard Carrera in the US. I've heard that there is a 'track' alignment which has less understeer, etc. Or did I hear wrong?

I've got a 1999 996 Cab and would like to have a 'neutral' alignment upfront, but don't want excessive camber on the rear.

Any pointers/suggestions?

[996noob]

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

- A caster adjustment is normally not necessary and is therefore not present! If required in a customer service matter, a caster adjuster may be installed (Serv. No. 40 19 23/Installing caster eccentrics).

- The toe-difference angle value is also influenced by the vehicle height! For this reason the measured result must be evaluated accordingly! No action is necessary in the case of small deviations from the toe-difference angle required value, as long as the value to the right and the left is almost the same.

I'm reviving an old, but useful, thread.

I would like to understand better the procedure for determining the ride height. Especially those who might be running adjustable height coilovers, the factory heights for various suspension versions may act as a reference for alignment.

I am having a little trouble interpreting Porsche's description of where I should be taking height reference from.

For Front height, the specs say "From road contact surface to lower-edge of hexagon bolt (a/f 18) of the tension-strut screw connection to the body".

Does "a/f 18" mean the hex size of the bolt is 18mm? Is the "Tension Strut" the front control arm?

For Rear height, the specs say "From wheel contact surface to the locating bore in the rear-axle side section (between toe and camber eccentrics)"

How does the locating bore look like?

I hope those who are experienced with this will be able to shed some light. Pictures would be even better! On my side of the world, the alignment guys aren't very experienced, so we have to guide them. These guys mostly do compact saloons with fixed rear axles and no camber adjustment, just front toe. And that's about 95% of the vehicles in the country.

Thanks!

[996noob]

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

- A caster adjustment is normally not necessary and is therefore not present! If required in a customer service matter, a caster adjuster may be installed (Serv. No. 40 19 23/Installing caster eccentrics).

- The toe-difference angle value is also influenced by the vehicle height! For this reason the measured result must be evaluated accordingly! No action is necessary in the case of small deviations from the toe-difference angle required value, as long as the value to the right and the left is almost the same.

I'm reviving an old, but useful, thread.

I would like to understand better the procedure for determining the ride height. Especially those who might be running adjustable height coilovers, the factory heights for various suspension versions may act as a reference for alignment.

I am having a little trouble interpreting Porsche's description of where I should be taking height reference from.

For Front height, the specs say "From road contact surface to lower-edge of hexagon bolt (a/f 18) of the tension-strut screw connection to the body".

Does "a/f 18" mean the hex size of the bolt is 18mm? Is the "Tension Strut" the front control arm?

For Rear height, the specs say "From wheel contact surface to the locating bore in the rear-axle side section (between toe and camber eccentrics)"

How does the locating bore look like?

I hope those who are experienced with this will be able to shed some light. Pictures would be even better! On my side of the world, the alignment guys aren't very experienced, so we have to guide them. These guys mostly do compact saloons with fixed rear axles and no camber adjustment, just front toe. And that's about 95% of the vehicles in the country.

Thanks!

Let me give it a shot. Please correct me at any point!

Front:

The Tension Strut is the Control Arm (No.3 in parts diagram) and the Hex Bolt (a/f 18) is the bolt securing the arm to the body in the front (No. 7 in the diagram).

Rear:

Between the eccentric bolt on Track Rod (No. 13 in the parts diagram) and the eccentric bolt on Control Arm (No. 21 in the diagram), there is a locating bore. What does the locating bore look like, and how is it measured against?

Thanks!

[panski]

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

Note:

- The following values relate to the empty weight, i.e. full fuel tank, vehicle with spare wheel/collapsible wheel and tools, but without driver and without additional weights.

- X74 = 30 mm lower. This can be identified by 1 yellow mark on the shock absorber.

- A caster adjustment is normally not necessary and is therefore not present! If required in a customer service matter, a caster adjuster may be installed (Serv. No. 40 19 23/Installing caster eccentrics).

- The toe-difference angle value is also influenced by the vehicle height! For this reason the measured result must be evaluated accordingly! No action is necessary in the case of small deviations from the toe-difference angle required value, as long as the value to the right and the left is almost the same.