Guys,
This is my first season running with race pads. Car is a 997.2.

I just finished my second track day running with PFC08's front and rear and both days (a week apart) were sunny and 70-80 degrees, DE events.

So my question is, do PFC08's squeal for anyone else when being applied on track? I would think they have enough heat in them with repeated 100-50mph stops after the firs session.

There was a black flag and when I pulled to the pits, besides the starter telling me what was going on the track, he mentioned I should check my pads because they were squealing loudly and he thought they might be running low.

Or do I need to adjust my braking?

 

I've never had track pads squeal once they're up to temperature, including PFC08's. Sounds like you need to pull the wheels and take a closer look. Also, don't just look at the outside pads with the wheels on and assume the inner pad is the same thickness. I've seen rotors stick where the outside pad looked fine but the inner pad was worn down.

 

That's what the starter said at the grid, I haven't looked yet, but the pads are essentially new (on the outside at least).

Everything seems fine, the car stops, and I tested different braking marker spots with not a big difference in sound.

 

They should not squeal bedded correctly. Did you bed them?

Bedding Brakes

 

Nope. I thought the PFC08's didn't have to be bedded. I put them in with brand new Sebro Coasted rotors.

I drove maybe 100 miles of regular city/highway street driving. Then drove 100 miles highway and tracked them for a day.

Then drove maybe 40 miles city/highway during the week, drove 40 miles highway to a track day on Saturday and they still squealed after session 5 (25min session) braking from 110 to 50 or so.

Maybe i'm braking incorrectly? I'm braking straight, getting my braking done before turning in...

 

My PFC08s on my 997.2 squealed ALL the time on track. In my experience, PFC08s start to squeal more once they are bedded in.

The issue I have had with PFC08s on two different cars is that they will "chatter" when not properly bedded in on a rotor that has been used with different pads. Once the pad is properly bedded in, it is great. The pads will start to really squeal at that point.

 

If you push the pedal harder, they'll squeal less. Seriously, the squeal is a high frequency vibration enhanced by any clearance between the piston, pad backing plate, friction surface, rotor and mounting ears. Without freshly resurfaced (or new, if specified) rotors and scrupulously clean components, it's hard to completely eliminate this.

 

Click on the link I provided above. It explains the physics and the procedure. Race Pads will ALWAYS squeal if your are too light on the brakes (like street driving).

 

The truth is 08 always scream. I love screamers !!

 

I use those pads and had furious squealing - track and street (my son wouldn't ride in that car anymore)! Then I changed front rotors to new, slotted... and magic!! NO more squealing...street or track!!

 

Good to know. I like slotted rotors for surface gas-off dissipation.

 

I use 08s and 11s with slotted rotors. No noise

 

totally quiet on track, VERY loud on street
08 front/ 11 rear

 

Hmm, maybe its brake residue in the rotor holes that's reacting with the pad and squealing.

All 4 rotors are new (2 track days on them) so I'm not replacing right now.

 

I just put in pfc08's with new ATE Cayenne rotors, bedded them in with a few 100mph>40mph runs, and now they squeal to ear-pain on the street. Haven't done track with them yet. Previously had Pagid Yellows with the same rotors and had zero noise both on street and track. Would it help to apply some anti-squeal brake paste on the back of the pads? Anyone done this?