Newbie handling question

[x5rap]

G'day. I'm new to the board and I just got my first Porsche after 20 years. My last was a '69 912, ex-E Production. My current one's a '99 996 coupe tip (Feb-98 build date) without the M030 sport suspension. The car has 35K miles on it. I'm really pleased with the car but the rear end "bobs" around a bit on entry into higher speed sweepers. It feels "uncertain". While it seems to track fine, it takes a bit to settle in and it's a little unnerving.

Does any one have experience with this sensation? Is there a reasonable modification to settle down the back end? Rigid sway bar links are available that replace the rubber-mounted links. In a street application, I'm concerned about the longevity of the rigid link with its spherical bearings or monoballs(?). In a race car application where spherical bearings are very commonly used, they're constantly checked. That won't be the case with a street car.

Is my experience with this "uncertain" feeling at entry a common one? Tire pressures on the 18" Turbo Twists are at spec. Does anyone have a suggestion besides the solid sway bar links? What about noise transmission without the rubber mounts?

TIA for your help.

[ADias]

I suggest you have your car suspension checked properly and the wheels aligned.

[Loren]

It might make sense to check the wheels on the car also. I saw a 996 with Boxster wheels in the rear once. They were 9" wide instead of 10". The car drove very light (and loose) in the rear.

[x5rap]

Thanks for the suggestions. Rears are brand new 265/35-18 Dunlop SP9090's. The wear pattern on the replaced rears was dead perfect and evenly spread across the tires, so I doubt it's alignment but...

I'll get the car in the air and have someone take a close look at the suspension.

It's great to have a Porsche again! Happy motoring!

[1999Porsche911]

The wear pattern on the replaced rears was dead perfect and evenly spread across the tires, so I doubt it's alignment but...

Sound like either your camber is not negative enough or you are running extremely low tire pressure. The rear tires SHOULD always wear more on the inside half due to the specified negative camber. Check the camber and set it to specs.

[ADias]

.... The rear tires SHOULD always wear more on the inside half due to the specified negative camber.

Loren: Is the above true?

[Loren]

.... The rear tires SHOULD always wear more on the inside half due to the specified negative camber. 

Loren: Is the above true?

Yes, pretty much so. The rear camber specs are -1 degree 10 minutes (for all Carreras except X74). Mine is set a little more aggressive at -1.5 degrees.

[b-man]

I'm really pleased with the car but the rear end "bobs" around a bit on entry into higher speed sweepers. It feels "uncertain". While it seems to track fine, it takes a bit to settle in and it's a little unnerving.

Does any one have experience with this sensation?

Is my experience with this "uncertain" feeling at entry a common one? Tire pressures on the 18" Turbo Twists are at spec. Does anyone have a suggestion besides the solid sway bar links?

TIA for your help.

<{POST_SNAPBACK}>

Please, no flames. But, what you are describing is normal in my opinion. These cars (with the base suspensions) have "soft" suspensions. If I had my way, I would simply go with shocks with a stiffer rebound valving. But, I just live with it for now.

b-man