After VIR South using R4S Porterfields... 2950lb car/4 piston/splash shields intact.

Will

 

Pagids tend to do this, though it's in a much more even pattern. The pad is basically leaving bits of itself on the rotor to grip onto. Looks like you were over the temperature range of the R4S's though.

You'll have to cool it down somehow, or run real race pads.

Warren

 

It's called carbon tracking or carbon tracing. Believe it or not, a lot of the components in a brake pad are there to REDUCE the friction, to make the pad more progressive and last longer. One of the components often used is graphite or other similar forms of carbon. if the conditions are right, the carbon from the pad fuses to the cast iron of the brake rotor, resulting in what you show in your picture. It's easy enough to remove by taking some sandpaper to the rotors.

Wow, I'm supprised I still remember that from when I co-op'ed with Rabestos.

-Chris

 

The interval of the dark spots looks consistent with ABS activity.

 

After much deliberation and frustration, I believe I have diagnosed your problem...

...it's a Volvo.

 

Volvo 4 wheel disc (since ~1966) ownz j00.

Per the ABS comment.... 1984 = non-ABS equipped 242.

Will
-who is thankful for all of the helpful comments

 

Volvo four wheel disc, rear wheel drive, twin piston front caliper STOCK

completely ownz j00!

 

My R4S's did that on the track too. I went to the R4 pads in front for track days and it went away.

 

I think the R4S pads I used at summit did this... I guess I would know for sure better if i didn't get down to the backing plates.. They worked a lot better with backingplate to rotor stopping power

 

me thinks that R4S's suxzor.

Will
-who will use blues on "da-box" next time

 

I've been saying that since the 1st session last VIR event...they SUCK!

 

, twin piston front caliper STOCK

correction, 4 piston


When you getting the I-6 supra motor sissy?

 

Okay, I am really losing it. Staring strictly at the rotor, I didn't see the two Volvo monikers and thought I was staring at some funky wheel on your ITR.

 

I can only wish for 4 piston brakes on the ITR...
Funky wheels on the Volvo = Ferrari units...

Per the I-6 turbo comment...
I can't keep brakes on a ~200hp I-4 turbo... How the puck will I be able to stop 600hp-700hp?

Will

 

Well, I certainly wouldn't use them for a track like VIR South...but don't throw them away either. They're a fine street pad.

 

I threw them away after 1.5 days of track time.
metal to metal =

Street use =
Track use =

Will
-who has learned better since that time

 

I can circle my 2600 lb Sentra approximately 3 times around VIR south with R4S pads before they give out. That track is just too hard on brakes to use anything other than R4, Panther +, or Hawk Blues.

The rotors on my Eclipe looked like that after Kershaw a few years ago.