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997S Alignment for DE, Autocross and street

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Old 04-17-2007 | 01:02 PM
  #16  
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...but also in those specs you should see a max variance for camber from side to side. I don't have my sheet with me, but you don't want it to be 0.5 degrees out side to side.
Old 04-17-2007 | 07:04 PM
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I talked with my service advisor this morning and asked him about the varience of the camber in my after set up. There is a difference of .45 degrees and he said that is actually not that much difference in camber. When I went in for the alignment I told him that I drive on the street more than track but I am planning on doing autocrosses and DE's with my local club this year and I wanted to get a better alignment for the track to help with outside tire wear but still have the car streeable. He said they would compromise and they do these type of alignments all the time.

I told him as the car is right now it has a slight pull to the right side of the road even when the road is flat and not crowned. My service advisor said the after alignment specs are where they should be for how I am going to use the car....mostly street and an autocross or DE once a month or so. He also said that if I had the camber for both side equal them the car would really pull to the right side of the road and I would have to maintain constant left steering pressure. That would really be anyoing on a 4 hour road trip.
Old 04-17-2007 | 07:56 PM
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here are the stock specs. as you can see porsche sets the max difference between right/left to 20' (0.33deg.) . don't agree with your service advisor "justification". if you are hapy with how the car is then this is what matters. enjoy it and have fun.
Old 04-17-2007 | 07:57 PM
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specs
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Old 04-17-2007 | 08:06 PM
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My alignment was out of whack at delivery so my dealer asked me how I wanted it... Street, track, or something in the middle. I asked for moderately aggressive street because it's 90% a street car and 10% a DE car. I'll have a great time on track no matter what the alignment.

I was told the most camber you can expect in stock form is about 0.80 front and 2.50 rear (or there abouts). I'm not even close to those limits - I wanted to start out soft and can always crank up later.

So, here's what they dialed in on the Hunter. Top is the "before" meaning how the car was delivered and the bottom are the "aggressive street" settings.
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Old 04-17-2007 | 08:40 PM
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Originally Posted by mdrums
I talked with my service advisor this morning and asked him about the varience of the camber in my after set up. There is a difference of .45 degrees and he said that is actually not that much difference in camber. When I went in for the alignment I told him that I drive on the street more than track but I am planning on doing autocrosses and DE's with my local club this year and I wanted to get a better alignment for the track to help with outside tire wear but still have the car streeable. He said they would compromise and they do these type of alignments all the time.

I told him as the car is right now it has a slight pull to the right side of the road even when the road is flat and not crowned. My service advisor said the after alignment specs are where they should be for how I am going to use the car....mostly street and an autocross or DE once a month or so. He also said that if I had the camber for both side equal them the car would really pull to the right side of the road and I would have to maintain constant left steering pressure. That would really be anyoing on a 4 hour road trip.
BS! Ask him if 50% differential in camber up front is acceptable, why didn't they set the rears accordingly? He's either uneducated in the ways of aggressive Porsche alignment, or flat-out lying to you. Remember service advisers are salesman not techs. Some are fabulous, others are less so....
As I've stated before on other threads, Porsche alignment specs are intended to keep you from driving your car aggressively. If it understeers, you won't go very fast through turns and that reduces the possibility of you crashing. It's all about liability to Porsche....
Old 04-17-2007 | 09:52 PM
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So you all feel that if I had my front camber on the left side closer to -1 degree to match my right side of -1.03 degrees then that would be better and all my alignment specs would be good for both street, autoX and track?
Old 04-17-2007 | 10:02 PM
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yep.
Old 04-17-2007 | 11:38 PM
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Originally Posted by doc2s
yep.
Ditto. Ive got mine at 1.5 fronts and 1.7 rears. I fully expect to wear out my rears in about 7k miles, fronts probably 10k or so. Those figures are completely acceptable and reasonable for the benefit of having a car that turns-in....
Old 04-17-2007 | 11:42 PM
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Originally Posted by mdrums
So you all feel that if I had my front camber on the left side closer to -1 degree to match my right side of -1.03 degrees then that would be better and all my alignment specs would be good for both street, autoX and track?
Having a 1/2 degree more neg. camber on the right side would be OK if you were running CCW on a heavily banked track....Are the streets in Tampa severly crowned? Wow, I'm really stretching to find a reasonable explanation for the offset....
Old 04-18-2007 | 12:33 AM
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Originally Posted by jrgordonsenior
Having a 1/2 degree more neg. camber on the right side would be OK if you were running CCW on a heavily banked track....Are the streets in Tampa severly crowned? Wow, I'm really stretching to find a reasonable explanation for the offset....
Nope the streets are not serverly crowned. I dorve around a lot today on the street and the car drives very nice and very very straight. I appreciate all the responce and help on this issue. I plan on seeking some other local advice. I might have my dealer just increase the camber to near even on both sides...which would be around -1 and leave it at that. I will call him again and see what he says.

thanks! Mike
Old 04-18-2007 | 12:38 AM
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Originally Posted by jrgordonsenior
Ditto. Ive got mine at 1.5 fronts and 1.7 rears.
from my understanding it is impossible to get -1.5 degrees of camber on the front of a stock 997S. I am told around -.8 to -1 is around all you can get stock.

How are you getting -1.5? Also I am told you want at least .5 to 1 degree differance of camber between the front and rear to help in over steer.
Old 04-18-2007 | 07:14 AM
  #28  
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Originally Posted by mdrums
from my understanding it is impossible to get -1.5 degrees of camber on the front of a stock 997S. I am told around -.8 to -1 is around all you can get stock.

How are you getting -1.5? Also I am told you want at least .5 to 1 degree differance of camber between the front and rear to help in over steer.
Probably because I simultaneously installed H & R lowering springs with the setup.

The advise regarding front to rear differences is probably correct if you're fighting oversteer but we're not. Our achilles heal is understeer. Try taking a spirited 2nd. gear 90 degree corner and you'll see what I mean. These cars are setup to push through a turn not oversteer. I would be surprised if you could make the rear end slide out without really trying like on a skidpad (great exercise everyone should experience). You will feel the front end slide across the turn instead on biting. Of course this is with PASM off since it will really screw things up and apply inside braking to make the turn. I should add that an empty parking lot is probably safer....
Old 04-18-2007 | 09:17 AM
  #29  
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0.5 deg difference will make the car more nuetral (less undesteer /more oversteer). with 1 deg difference the car will have more underteer.
Old 04-18-2007 | 10:07 AM
  #30  
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Originally Posted by doc2s
0.5 deg difference will make the car more nuetral (less undesteer /more oversteer). with 1 deg difference the car will have more underteer.
Mi no comprende.... Are you saying about the difference side-to-side, or the difference in neg camber from 1/2 to 1 degree?

If it's across the fronts, wouldn't that be dependant upon which directon the car was turning?


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