yebokmj

I had hoped with the upgraded rotors it would allow me to run a less aggressive pad that would be fine on the streets as well. I've run the DS3.12 and they were fine but I did encounter Ice Pedal a few times. The Hawks I've never encountered Ice Pedal giving me the confidence to brake deep. Plus the Hawk's are free replacement at FCP Euro

Kitc2246

I DE a 2013 Boxster S with PTV. Had an 09 Boxster before. I don't particularly notice PTV working, however I never drove the car without it. The right rear pads wear quicker than the left. Not a huge amount, but a noticeable difference so its doing something at the mainly clockwise Summit Point. I can see where the PTV would change a track out since it is braking the inside rear to help rotate the car. IMO the comment on working overtime to limit spin would be PSM and ABS, nothing to do with PTV although it might be trying to do its thing at the same time.

I use Sebro slotted and Pagid RSL29s (yellows) from FCP Euro. On my fourth set of fronts and have a set of front and rear pads and rotors to warranty. I wore out a set of DS1.11s in six track days and had planned to move to 3.12s when FCP Euro offered the Pagids. Suspect the Ferodo 3.12s are a slightly better track pad, but the Pagids work for me especially with the warranty.

BondJ

Respectfully, ABS only activates when pressure is applied to the brake pedal.

PSM, which operates via the ABS module, will only intervene if the various sensors monitoring the car’s steering angle, speed and direction, yaw rate, lateral acceleration rate, wheel rotation speed, steering wheel angle and position of the brake and accelerator pedals are deemed to be incorrect (i.e. oversteer/slide). This does not apply when simply cornering hard.

PTV is designed to work in conjunction with a LSD which acts as its control. Without this control the inside wheel will drive without restriction, forcing PTV to over compensate.

IMO the excessive brake application of the inside wheel, as described above, is due primarily to PTV activation without LSD

Kitc2246

"Working overtime to limit spin" would cause ABS to intervene via PSM was my point which I still stand by. Your second statement supports that.

BondJ

No it doesn’t. ABS will not operate just because the wheels are spinning under drive, and PSM will not intervene simply because the car is cornering hard. The coding of PTV without the control of the slippy is the issue

KNSBrakes

Using the rear brakes to aid an LSD might be helpful to new driver's but limiting to more advanced drivers.

I know it's not called PTV on 987.2's but next time you're at the track go look at any 987.2 track car and tell me what color their rear calipers are.

Wish I could turn it off on 987.2's- even with TC off and sport plus (PDK) the rear calipers turn purple with a good driver after one day on the track.

--Aaron

nhnguy12

I haven't attempted turning it off on 987.2 car. PIWIS 2 should be compatible with those cars though.

Cayman Ed

Thank you Nam for your discovery & contribution on GT3 EPS calibration and PTV activation via PIWIS
Question: I read that rear brake pads wear at faster rate than normal, does it mean that this activates the inner rear brakes only?

Jim981CS

Yes as described below, “ when the car is driven assertively into a corner, moderate brake pressure is applied to the inside rear wheel”……
Jim



From Cayman 981 sales brochure

HenryPing

Hey, @nhnguy12 , do you know how to reach that specific page for the PTV in PIWIS 2 shown in your OP? I don't know German and was lost

Thanks
Henry

nhnguy12

If you go to the Overview page that lists all the modules it'll be under the PSM/ABS module if I remember correctly. Make sure you go into coding without rules to find all the available settings.

Cayman Ed

I have a 2.7L PDK Cayman 981 with X73 rear anti-sway bar installed only and I would rate my driving skills as between novice and expert. I do push my car when opportunity is safe and never tracked.
Do you agree with me that adding the PTV without the mechanical LSD will only grab power down due to application of inner wheel braking to the already lesser 2.7L during spirited & aggressive street driving?
Tks.

nhnguy12

With spirited street driving I haven't found that PTV applies enough brake pressure to sap any meaningful speed. PTV also seems to work mainly during steady throttle and coasting, so engine power is not too relevant to PTV's functionality.

Jim981CS

I found this information on the PTV and PTV Plus on the 911 which gives more detail on its operation than the screenshot from the Cayman I posted on post #39 above. This states that selective breaking is applied on the inside rear wheel as soon as the steering wheel is turned……and goes into more detail.
Jim

nhnguy12

Another useful piece of literature outlining all the electronic systems in play. Worth noting that several systems here besides PTV are at least partially responsible for adding heat into the rear brakes with hard track use.

Also worth noting that even Porsches with open diffs come with automatic brake differential (ABD). That would explain why a lot drivers don't miss the presence of a mechanical diff in the majority of use cases. McLaren uses a similar brake-based system with an open diff even in their flagship cars.