From the order guide, PTV: Actively enhances the driving dynamics and stability by enabling variable distribution of engine torque to the rear wheels and mechanical limited-slip rear differential. Depending on the steering angle, steering speed, throttle pedal position, yaw velocity and vehicle speed, PTV optimizes steering response and precision by applying brake pressure to the left or right rear wheel as required.

Any thoughts on how PTV might adversely affect rear brake longevity when used on the track? We all know heavy track use can quickly chew through the rear pads. I wonder if PTV might make things worse. I am thinking PTV + track time + PCCB's = costly proposition.

 

Depends on how much track time you do and what your intent is.

Personally I wouldnt get PCCBs on a track/street car because the cost of replacement parts is significantly higher for a marginal overall benefit.

As for the PTV you are going to get a ton of comments in either direction, from my experience on the track the standard PSM on the turbo is fantastic. It lets you get plenty sideways safely before kicking in.

The turbo's problem is understeer which after suspension work wont be corrected because its AWD and much heavier in the front than a RWD 911.

That in mind the point of track time is to get more familiar with your car and explore its limits, the PTV, if it works as advertised, will make you go faster, but wont give you any additional skill, which to me defeats the point. I dont care if Im the fastest on the track, I care if Im improving my abilities.

After tracking my car for two years I've taken it as far as I can safely go and I dont feel comfortable driving a 100K street/track on the limits with the safety gizmos off so now Im looking for a dedicated track car (E46 M3) that I won't cry about if I happen to go off. Not to mention it'll allow me to explore car control in a much more predictable manner given that its front engine and not so rear weight biased.

If you are planning to do some serious track time I would skip the PCCBs and the PTV, drive with PSM on, it wont intrude in any but the most dangerous situations, and then once you get really fast, you'll upgrade to a track car because you'll want to explore the limits.

 

I agree that PCCB is not a good idea for a track car.

For PTV, in theory, yes possible the brake may/might be worn prematurely. But note that cars that have this system, the fugly GT-R and Mitsubishi EVO for example, have not had any problem with brake wear. Well not that I have heard of anyway. Anyone please correct me if I am wrong on this.

To me PTV is potentially a revolutionary change to 911's handling and might be part of the secret as to why that 3900 lbs GTR could take corners so well. No formal review yet, but without a doubt, I want this. LOL

Does anyone know if PTV could be turned off?

 

The documentation I read said that PTV could NOT be turned off.

 

Weren't the rear brake wear problems caused by tracking with TC on? Thought I read that turning off TC was the solution.

 

Larry - in 997.1 this is true although some will argue the problem is not with TC it's with the driver. Put, PTV is a separate system in the 997.2 that cannot be turned off.