runet

I have a strange issue regarding front camber adjustment on my GT3. The car had different amount of shims on left vs right LCA when I bought it, but this winter I finally installed the same amount og shims on both sides - 14mm.
- Car has OEM LCA's, same part number on both sides for both inner and outer part. Looks like rubber bushings, not monoballs.
- Ohlins TTX dampers. Ride hight adjusted an just 1-2 mm difference due to corner weighting.
- OEM top mounts, not rotated.
- On one side only able to reach -2.3 degrees with max adjustment in strut tower.
- On the other side, -2.3 degrees is achived with minimum adjustment in strut tower.

So with everything installed and adjusted symmetrically and having the same camber on both sides, the strut tower adjustment is on opposite extremes.
No sign or information suggesting damage to the car at any point.
Caster is fine on both sides, just above 8. Toe-in 0.0 on both sides.

So the alignment is ok to use, but with 14mm shims I would like some more camber for track but can only achieve that on one side. Seemingly able to reach at least -3 degrees on one side without rotating the strut mount, what can cause such a big difference at the top mount/tower adjustment left and right?

Have searched the forum, but besides a similar unresolved issue on a 991 GTS and also in the rear of another 997, this does not seem to be a common issue.

Any ideas?

audipwr1

Bent upright

Spyerx

some minor variation is normal but that seems like a bit.
could be another bent part
i want to say mine varies a bit with the shims side to side
but if you want more camber rotate the hats.

CRex

My guess as well.

Gptoyz

+1 bent

is caster equally messed up? How is your trust?

runet

Caster and other angles are fine and within spec. Can such big difference from side to side be caused by bad rubber bushings?

On the right side where there is no more adjustment range available on the strut I have less camber than last year, despite having added 1mm more shim and the car is sligthly lowered since then. This make no sense to me if even if the upright should be bent. When I bought the car it was even lower and with more camber than what I can achieve now.

Bad alignment equipment? Maybe I need to recheck.

balefire

I've had this on two previous cars, a 996 40th and my rx8. No prior accidents. No suspension abnormalities. I push the camber to max on all my autox cars. This problem is not normal or ideal but not uncommon unfortunately. You can try to loosen the subframe to equalize it but nothing else. I just ran it unequal and rotated the tires frequently.

runet

Thank you - this might very well be a clue to the cause of my issue. I removed the front subframe when I installed my euro 90l fuel tank before last season. There is really no adjustment for the subframe, but I guess removal and reinstall might be enough to cause the camber to be uneven from side to side now.

Gptoyz

Sorry I meant thrust angle

Spyerx

Ah yeah, the subframe... yes for sure could cause. Are you running all monoballs? including in the lower control arms? The rubber can distort but your does seem a bit. On my old cars its more pronounced.

I know when I drop the motor they always need to re align/toe check the rear due to the subframe. It always needs a bit of adjustment.

runet

Seems that the inner LCA bushings are monoballs after all, took a closer look today. Unlikely they are contributing to the problem then. Guess the most likely reason is the subframe being reinstalled. Thrust arm bearing is solid with adjustment, and caster and other angles are as they should be.
Will check everything again anyway, also doing another alignment at a different location just to be sure it's not the equipment being the reason. The car is excellent to drive so it's not like this has been a practical issue, just the numbers not being as excpected.
Thanks to all for the feedback.

pete95zhn

+1. BTDT There's very little movement on subframe, so no real help from wiggling it. Bent upright is very difficult to detect visually, the only way (apart from strange alignment figures) is to dismantle them and place on the table hubs down. Strut holes should line up. Of course one way to find out things is to look diagonal and control arms for manufacturing dates. If different from side to side, the car's been hit on one corner...