Front end gets really light above 90

[steve20186]

I had an occasion to bring the car up to just past 90 a few days ago.  At about 92, the front seemed to be really light.  Is this 'normal'? 

[EleCTriCT]

90 mph is a decent clip,

 

assuming your vehicle is road safe and does not have loose suspension bits,

 

tires, pressures, alignment and shocks come to mind.

[rngtrtl]

I had an occasion to bring the car up to just past 90 a few days ago.  At about 92, the front seemed to be really light.  Is this 'normal'? 

I would say no, not normal. These cars were made to be driven on the autobahn at speeds almost twice that... I routinely get mine up to 120ish and it is solidly planted.

[Fluke996]

Mine felt light at those speeds and higher, replacing standard front bumper cover with a GT3 cover added downforce, and it felt more stable. If all your suspension parts check out Ok, then you may want to look into the aerodynamics.

[steve20186]

I've checked the suspension on a lift before getting a recent alignment and everything seemed tight.

 

I did fnd another road and got it up to 101.  This time I was more conscious of the steering and it felt stable.  I think the other road I first tried - which I normally drive 55 on - there are slight pavement wallows that - when going 90 are amplified and make it feel unstable. 

 

I really need to do a PCA DE track day to get a better feel for this car and it's capabilities though.

Edited July 3, 2014 by steve20186

[Dennis C]

I had the opportunity to drive a new 997 (I know, it's not exactly the same) on the autobahn in Germany a couple of years ago.  The fastest that I went on the unlimited speed sections of the autobahn was just over 240 kilometers per hour, which is roughly 150 mph.  I noticed that the front end of the C2S that I was driving got a little "floaty" around 150 km/hour and it stabilized around 175 km/hour.  I found this to be the case on multiple occasions.  I think it's possible that what you're experiencing is normal.  

[Ubermensch]

It's a fairly common complaint on the 996s. As was mentioned, the two best solutions are the aero front bumper and/or lowering the suspension a little.

[White987S]

Like suggested above and a few more:

 

Alignment

Good tires

Tire pressures

Maintained suspension

Matching tires

If directional tires, are they correct

Rear spoiler- proper function

[Domiac]

After I had my 996 (Carrera 4, 2004, 86k miles) raised in jack stands for multiple months, I assume my suspension took a hit. All tires are in a really good condition, pressures are good. Just changed my engine mounts.

 

When I drive around 50mph to a curve, accelerating hard but still without losing traction, the car rolls considerably and my front feels really really light. Doing quick steering movements on a 40+ mph speeds is scary. The difference is drastic when compared to the time just before I put my car on jack stands. Could it be that my spring coils took a hit?

 

I'd be happy to start another thread, just let me know. Otherwise, please throw any ideas how to check or measure my suspension. I'd also like to inspect it myself before I drive my car to Porsche shop. I know engines reasonably good but I am a newbie to suspension.

 

Thank you!

Edited July 10, 2014 by Domiac

[steve20186]

No need to start a new thread on my account.  

 

I assume that your stands were under the chassis letting the suspension hang?

[Domiac]

No need to start a new thread on my account.  

 

I assume that your stands were under the chassis letting the suspension hang?

 

Yes. Multiple times I had a thought that I probably should raise suspension a bit too to relieve stress but I never got into it :-(

 

To my understanding I have jacked the car always from proper places. I have removed my engine & transmission twice and the car has been on jack stands for around 3 months or so in total.

[Domiac]

Noticed today that my front left fender is almost 10mm / 1cm higher than front right. Back fenders are at identical height. Took measurement multiple times on different locations, car was level. Definitely something is off on front suspension.