E_T

So, last year in October I took delivery of a beautiful C2S (my first P-car and only rear engined car I have ever driven) that I bought in the US and had shipped over to Austria, where I am currently living. The car was in mint shape inside and out, 21 K miles on it, arctic silver, sports seats, LSD, sports suspension etc., basically all the bells and whistles I wanted, really. (pictures here, if anyone should be interested: http://www.aceautosports.com/wordpre...-011-large.jpg) . Getting it approved for use in Europe took a while (Porsche in Austria changed the blinkers, added the rear fog light etc.), so I only really got around to using it very briefly before the winter proper set in.

There was one issue with the car, the tires were old (now changed to new Contis). Thread wise they were fine, they looked as if they had hardly been used, but I suppose they were brittle. On a trip up to the Hölental, on beautiful scenic alpine roads, we approached a 90 degree turn, at not much speed at all, I am guessing around 20 mph hour, and probably lifting off the throttle, the car does a 180 (+), just barely escaping the rock face and a metal fence / river. The road was wet, but not soaking, and frost was not an issue.

The drama of the incident – and I hate to admit this – is that it spooked me, almost to the point where I am hesitant to take her out, especially on more spirited drives. I (now) know that I should never have lifted the throttle, got the breaking done before the corner, not driven on old tires and in the wet, and should sign up for a course to learn how drive the car at and over the limit on a circuit. Anything else that I could consider to restore confidence? Does it sound like throttle lift off oversteer to you? This is at least what I suspect, but reconstructing the incident is a little hard eight months down the road. I got off to a bad start, and would hate to have this happen again.

cmat

The old tires certainly contributed but I think you need a good front and rear alignment from someone who knows 993's. I had a smilar issue in the wet with my car and an alignment transformed it.

certz

I would recommend an alignment by someone that is familiar with 993's. This sounds a lot like an issue with the kinematic toe. A bad alignment and especially a bad kinematic toe alignment can make our cars a nightmare to drive. When I first got mine the K-toe alignment was bad and the car felt like it was going to spin at every turn - especially ones where I was carrying any kind of speed. Not very confidence inspiring. Once I got that fixed the rear felt planted.

E_T

Alignment it is, then, or at least have it checked for inconsistencies. To be honest I have to read up alignment and kinematic toe. When I had the tires changed the mechanic - from what I gathered - looked at it, and gave me a series of numeric values and said it was fine. I will dig out the paper but as said the values have limited meaning given my limited knowledge on the issue, but I will definitely look into it. Many thanks.

TravisB

Had a very similar experience in my car not long after I bought it..it had mis-matched tires and the state of alignment was unknown. Tires and a good alignment really did wonders, I think you will probably experience the same!

Reddy Kilowatt

Had a backwards off with mine also. Sounds like you think you lifted, though 20mph doesn't seem very fast. Mine was probably too much throttle exiting a corner with sketchy traction. Get the car aligned and planted, get good tires on, and spend some time autocrossing or tracking it. Professional instruction is good. The confidence will come.

Mark in Baltimore

Excellent advice, and it sounds like you understand that proper high performance driving education is in order. Skilled drivers can overcome a multitude of mechanical issues, not to imply that you should live with any shortcomings.

E_T

Thanks for all the advice, much appreciated. I am still puzzled that lift off caused the spin, given the slow pace entering the turn. I am thinking that there might have been some grit on the road that might have amplified the problem, but still...12 year old tires probably did not help much, either. The guy I got the new tires from
races old 911, and definitely overcame any mechanical issue I might have had, power sliding the car two rounds in a roundabout with the old tires..

ABCar

E T
Trust us, these are rear engined cars and prone to lift-off oversteer but not at the speed or conditions you described. Once you address alignment and tires you will love the handling around corners at much higher speeds. This behavior you described will only occur much closer to the limits of adhesion with all else good.
Enjoy your car with confidence and get it aligned and re-tired soon.

RocketJohn

i don't know how you could do a 180 only going 20mph... either ice, or completely shot tires and/or terrible alignment settings would have to be the reasons...

I would find an instructor for some one on one training at a local grand prix style track in your area and spend a few hours gaining your confidence back... especially now that the temps are warmer and you have new tires... check your alignment too... nothign builds confidence like driver education...

Linnm

Why not contact Porsche and ask about their "High Performance Driving Course"

TravisB

Yeah my situation was close to identical, though the tires weren't as old (6-7 year old Michelin Pilot AS in front, new Sumi HTRZ-II's in the back). Go in to the banked turn through a short tunnel, I don't think I lifted...all I know is one second everything was fine, the next I was facing the wall of the tunnel with two passengers in a state of paralysis.

The next day I was heading in to work in the rain and had a different banked turn that I went in at a normal pace; it got really squirrelly on me again (but I was prepared for it this time). I took it in to Cantrell for tires and an alignment the next week, and it was a totally different car, especially in wet conditions.

I can say with 97% certainty those two things will transform your car..then of course get to the track for some of the most enjoyable learning on the planet!

E_T

Thanks again, guys. These Porsche performance driving courses cost an arm and a leg (well over 1000 euros), but are worth it if the alternative is losing one.

I just checked the geometry figures I got when the tires were changed: I was told it was all good. My German sucks, but I take it that these are camber values -0,40 degrees and -0,45 degrees front left and right respectively, -1.30 degrees and -1,35 degrees left and right rear. Not sure what "gesamtspur" means, but it also says that this value is 2 mm at the front and 2,5 mm at the rear.

E_T

Come to think of it, I have a video of the events leading up to the spin, cutting literally a second before the rear end comes out. My friend was filming with his iPhone. Spin not in, it cuts just before. Two seconds later we were facing the opposite direction.

http://www.youtube.com/watch?v=9rofd...ature=youtu.be

Not quite sure how to embed, so posted to YouTube.

Mark in Baltimore

Use "[y t]YouTube code after equals sign easiest to click on "embed" and copy and paste the code[/y t]" but make sure there are no spaces between the y and the t.



Is that gravel on the road or sleet that I hear? Regardless, in combination with damp roads, cold temperatures and dry rotted tires, it's no wonder you spun at such a low speed.