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Discussion Starter · #1 ·
I recently installed PSS9's in my 05 Boxster S (non pasm).

Ride Height:
13.7 (F) ~ 1.3" drop
14.25 (R) ~ 1.25" drop

Damp/Rebound: 5 (F/R)

I'm looking into getting the alignment re-done with proper corner balancing etc as I don't think the original aligment shop has to much extensive knowledge with Porsche + performance mods.

Alignment:

Front Left/Right
Caster 8.1/8.0
Camber -1.2/-1.2
Toe 0/0
SAI 18.6/18.0
Included angle 17.4/17.1

Rear Left/Right
Camber -2.5/-2.5
Toe 1/32 / 1/32


I would describe myself as spirited street driving, with good amount of straight HWY use too. During the summer months I would estimate 1-2 track days per year. Therefore this car spends most of it miles on the street.

I'm a bit concerned I have to much negative rear camber, which will lead to dramatic increase tire wear, any input? The install shop is suggesting camber plates to reduce the negative rear camber, is this really my only solution or will an alignment tech (familar with Porsche) be able to reduce my neg rear camber?

I would like some input before spending more $ just based on shop recommendations.

Thank you!
 

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You are right; 2.5 rear camber is too much for your driving.
You should have the rear withing 0.5 of the front or 1.7 which is in the stock range. I don't think I ever hear of camber plates in the rear. Somethings wrong if they couldn't get less camber than 2.5. Go to know Porsche shop to see what going on here.
 

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I tend to agree with Augie but I don't think -2.5 will result in severe wear. Lowering the car probably adds about .5 to .7 degrees negative. I would think that you should be able to get back to -1.7 with the standard adjustment range. When you change the camber, you will have to correct toe again. Any one familiar with Porsche alignment should know this.
 

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During street driving, I haven't seen any excessive uneven wear due to camber; I ran cars with -4.5 to -6 camber front or rear, never had issues. However, toe will wear out tires much more unevenly, but I don't think your toe is excessive. At the same time, have 0 toe in the front will increase tramlining and make the steering touchy on the street depending on the conditions of the streets/highways.
 

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If it were me, I'd want to bring the rear camber closer to the front to reduce understeer. I agree with the 1.7 suggestion above.
 

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During street driving, I haven't seen any excessive uneven wear due to camber; I ran cars with -4.5 to -6 camber front or rear, never had issues. However, toe will wear out tires much more unevenly, but I don't think your toe is excessive. At the same time, have 0 toe in the front will increase tram-lining and make the steering touchy on the street depending on the conditions of the streets/highways.
1) how did you get that much camber ?
2) how much street driving it you do with this setup ?
3) I find it hard to believe you wouldn't get tire wear with that setup.
 

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I run -2.5 / -2.5 and I haven't noticed much excess wear on my tires. I do about 4 DEs (on separate tires) and 15K street miles a year.
 

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Discussion Starter · #8 ·
So I just want to confirm even though I have no other special mods such as control arms etc, my rears should be easily brought up to -1.7.

By chance does anyone know more specifically what a Porsche tech alignment would do to make this happen vs just a regular alignment shop tech?

I've now noticed dramatic tire road noises such as slight howling etc at HWY speeds especially, I'm assuming this is normal based on my current align settings?

My tires etc have pretty good tread life (and I didn't drive it much b4 the alignment), prior to the lowering it was relatively quiet on the HWYs.

Thanks for the input!
 

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I run -2.5 / -2.5 and I haven't noticed much excess wear on my tires. I do about 4 DEs (on separate tires) and 15K street miles a year.
I'm really surprised to hear that.
No inside tire wear ? How many miles do you get on a set of tires ?
 

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KnightTKD, the only rear camber adjustment is the eccentric screw on the inboard end of the LCA. Any technician should be making adjustments here. With no mods to the rear suspension, I had -2 with the screw maxed .
 

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1) how did you get that much camber ?
2) how much street driving it you do with this setup ?
3) I find it hard to believe you wouldn't get tire wear with that setup.
1) This was on Subaru STi, Evo VIII and 350Z with coilovers+camber plates+eccentric bolts. Those cars needed that much camber to use Hohos effectively. I don't think the CS needs that much, but I am not sure exactly how much it would need.
2) each car got about 10-12K miles per year.
3) believe ;) On the street, of course, I used street tires with 140-200 tread wear rating, with such hard compounds, you don't have to worry about camber, but as I said, toe is quite impactful, both positively and negatively.
 

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1) This was on Subaru STi, Evo VIII and 350Z with coilovers+camber plates+eccentric bolts. Those cars needed that much camber to use Hohos effectively. I don't think the CS needs that much, but I am not sure exactly how much it would need.
2) each car got about 10-12K miles per year.
3) believe ;) On the street, of course, I used street tires with 140-200 tread wear rating, with such hard compounds, you don't have to worry about camber, but as I said, toe is quite impactful, both positively and negatively.
Wow. Like Auggie, I too would've said it's not possible to run -6 degrees of camber on the street without wearing the insides of the tires. I'll take your word for it, but something seems odd. (Definitely not recommended on a Cayman). Regards.
 
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