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Pulling behavior on acceleration and deceleration

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Old 05-31-2011, 08:40 AM
  #16  
StevoUK
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Tyres recently fitted will do this, suspension and tyres need to settle.
Also the releasing agent on new tyre treads will compound the problem.
This effect goes away after a few varied road miles.
Old 05-31-2011, 08:41 AM
  #17  
Dervish
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Originally Posted by early_grayce
+1
get a second opinion on your alignment.
+2, sounds like alignment out.
Old 05-31-2011, 09:40 AM
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faster
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Competent alignment has taken place in the beginning correct?
Old 05-31-2011, 10:13 AM
  #19  
Dervish
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Originally Posted by faster
Competent alignment has taken place in the beginning correct?
Dealer does not always equate to competent. You should be able to stand on the brakes (in a straight line) with no hands on the wheel with a good geo alignment. Get a second opinion on it by a specilialist and I'm sure the problem will surface. You may have a slight 'crabbing' which is not evident on tyre wear.
Old 05-31-2011, 11:26 AM
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MetalSolid
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You need a proper alignment -- for some reason dealers are incapable of doing this -- specifically, your 'thrust angle' is off (rear toe).
Old 05-31-2011, 12:03 PM
  #21  
spare tire
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As everyone said "1. Alignment, CPO is unrelated to Alignment. Go to a local good Porsche Race Shop and ask for before and after alignment settings."
Old 05-31-2011, 03:05 PM
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Had the exact same with brand new PS2 tires. Swapped the rear set with a used second set i have with MPSC. Problem gone. Tires went back to the shop and got new PS2 tires. Problem solved. Drive's perfect now.
Old 05-31-2011, 09:49 PM
  #23  
TomGT3
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I had the exact same problem. Happened because one front tire (damaged) was newer than the other.
The problem was found when I had the fronts swapped and the car pulled the other way. After changing both, problem solved.
Old 05-31-2011, 10:53 PM
  #24  
lfish
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Taking car back to dealer this week armed with your suggestions/analyses. Thanks again, will post what the outcome is, hopefully a stable, well behaved car which is a blast to drive on the track!
Old 05-31-2011, 11:08 PM
  #25  
FFaust
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Looking forward to the feedback.
Old 06-01-2011, 12:22 AM
  #26  
faster
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Sorry Long Story....PPI founded a nail in one of the rear 700 mile (Michelin) sidewall, P.O. purchased a new one after an exhausting search of the USA. He removed the wheel at home, took it to the Porsche Stealership and had the new tire mounted. The car was never driven again except to load it in the trailer in front of his home. Move ahead....... my first drive....ran it thru the first 3 gears pretty briskly and thought WTF. The car pulled to the right on acceleration and when the clutch was disenged to shift or power off, it violently veered to the left, sometimes into the other lane (tire pressure all checked good) dismounted wheel and swapped location, did the same thing, but veered right. The P.O. swore it drove perfectly and so did PPI Tech. P.O. knew his neighbor had a slightly used take off from a recent GT3 he had just sold which he purchased and shipped to me. I removed the new one and mounted the used tire and waalaa problem solved.... who would have thought?? Some 6-3 owners and a friend that works for Porsche Racing was leading to diff issues, but I just didnt want to believe that with the low miles and not tracked and nothing had changed prior to purchase except the tire.

Last edited by faster; 06-01-2011 at 01:00 PM.
Old 06-01-2011, 03:32 AM
  #27  
Bluetengelb_GT3
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First post but here goes

Had same type of behaviour on my Mk1 996 GT3 last year. Suspected diff, checked tyre pressures, alignment. It still persisted. Turned out that one of the rear shock absorbers was shot, so it pulled left / right in acceleration or deceleration.

With your low mileage this seems unlikely, but it is worth checking if the other things don't solve the problem.
Old 06-02-2011, 10:48 PM
  #28  
faster
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[QUOTE=Bluetengelb_GT3;8601714]First post but here goes


Welcome!
Old 06-03-2011, 12:41 PM
  #29  
Rob in VA
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Same problem for me. It was a worn out strut. Make sure none of them are leaking.
Old 06-07-2011, 09:31 PM
  #30  
dan212
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These are OEM tires? I Would replace them on based on age alone and only then diagnose if the problem continues. This is OLD rubber


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