orthojoe

I was contemplating last week whether or not to change my brake pads since they are getting close to being worn out and was presented with an opportunity that pushed me to just go ahead an swap out the pads. Essex Parts has asked me to test out new rotors and brake pads designed for the 991 GT3. Most of us are familiar with PFC, Pagid, and Brembo, but I don't believe many here are running AP racing rotors or Ferodo DS1.11 brake pads. Competition is always good, and I have the opportunity here to test out something new to see if it's up to snuff for us track addicts.

So, I went forward with the painful process of a brake job on this car. Here is a pic of the PFC11 pads after 8 track days and 986 track miles mostly at Thunderhill and 2 at Sonoma. None at Laguna Seca.

Here are what the front PFC11 pads look like:



You can see that there is no problems with pad tapering, but the inner pad seems to be more worn than the outer pad.

Here is how much pad is left compared to a new pad:



Here is a pic of the rear PFC11 pads compared to a new set of pads. Not much wear:



Here is a closeup of the OEM rotor. Still in good shape with only minimal cracking:



The dust boots on the calipers are cracked, but no surprise there:



A nice improvement on the 991 is that you don't need to install the 'nubbins' that mate to the centerlock wheel on the rotor anymore since they are mounted to the hub. On the 997, they were a one time use and needed to be installed onto the rotor. Not on the 991:



The parts:


AP rotor:


The nice thing about these rotors from Essex is that they are pre-burnished/bedded with the selected pad material so you don't have to go through the painful and difficult process of bedding/seasoning your rotors before taking it to the track. I weighed the brand new AP rotor against the used OEM rotor. The AP rotor comes out the 24lbs, and the OEM rotor weighed 23.5lb. I'm assuming some weight loss from use, so the weights are essentially the same between OEM and this aftermarket rotor.

Installed:



My buddy helping me with holding the brakes and the steering wheel while re-installing the centerlocks:




Done:



Total install time for pads on all 4 corners with front rotor replacement was 2.5 hours. It's a lot more time consuming than any other car I've worked on in the past, and very tiring (either that or I'm getting old). I'm not a fan of these new brake calipers and the centerlocks at all.

I'm headed to the track this Friday and will report back on how the new brake setup performs. I will run them to the end to see how many days I can get out of them. Thanks to Essex for the opportunity.

Mech33

Nice, thanks for sharing! So when is your first track day with the new rotors and pads? I was about to pull the trigger on some PFC pads.

Feeling any better or worse about the caliper studs now after swapping the brakes another time?

orthojoe

Will be headed to thill this Friday.
The caliper studs were nice to have. They might have saved me only a few minutes in work time, though.
The biggest time consumers are 2 bolts that hold down the hard brake lines that need to be released from each upright (the front uprights take the most time), and the center locks.

MayorAdamWest

Very nice! I'm really interested in the result, given my mixed experience with the PFC11 thus far.

Alan C.

Joe, that second photo of your assistant looks like he might be a fierce competitor someday.

orthojoe

LOL

MayorAdamWest

I'm surprised he could hold it down. I had a full size adult do it, and it was still quite difficult to keep the wheels from spinning.

orthojoe

The key is to turn the engine on so your brake booster and power steering are on.

kshu1991

Have you consider the brembo rotors that sun coast part sells on their website?

orthojoe

I used them on my boxster spyder pccb conversion.
They only lasted 12 track days. I expected more for how much they cost. They only lasted 12 days on my friend's 997.2 GT3 too. In fact, the pads outlasted the rotors. I wanted to give something else a try. I will report back on how long they last and how they perform

MaxLTV

Surprised at how much pads wore, but the rotors look great. The new set up is very interesting, especially if the price is right. I doubt it will have any performance issues, so it all boils down to price vs. longevity. Also, 2.5 hours for pads & rotors is not too bad. Even with top-loading pads you would need to remove caliper for changing rotors, so I would not expect it to be much less than 2 hours even with ideal set up. But maybe I'm just slow with mechanical stuff.

orthojoe

You're right that with the rotor change, you lose the time advantage that open top calipers have for pad swapping. However, from a pad swap only standpoint it's really bad. I've clocked a 4 corner pad swap on my old BRZ in 20 minutes start to stop. The centerlocks and the brake line brackets are what really slow down the process. The other stuff is moderately longer. Compressing the pistons with a girodisc spreader used to be a snap. Now you have to maneuver the spreader into the caliper while it is hanging on a bungee cord behind the brake rotor.

Bartron

For all you guys doing your own work, where do you find the torque specs for all the fasteners. For motorbikes, they're usually easily available in the manual.

Is there a shop manual for these cars?

(My manual and books have not arrived yet to join the car so perhaps they're in there...)

orthojoe

The nuts for the caliper studs are specified by Tarrett at 54ftlb (caliper bolts are 67ftlb)
The centerlock is 443ftlb
The 10mm bolts holding the brake lines are just hand tightened
The seat bolts are 37ftlb, which I used from prior gen Porsches. The seat bolts are the exact same, and so is the bolt pattern

Spyerx

Never understood why you got so little life. These things are lasting me forever. You are a bit quicker. Were they cracked to the edge? I have a set of rings I thought were done but brembo,engineer stated they were fine.