s2000ellier

i thought bbk's were str legal, thats your best bet.

CKit

XP10 isn't really even a track pad.
The other thing to note is that once you get down to 1/2 pad or so, the wear really accelerates.
To the point where I won't even start a session with less than 1/3 pad.

gptoyz

You are overworking your front pads by using a pad bias.

#1 ditch the slotted rotors and go back to blanks

#2 run a square pad compound xp12, hawk dtc 60, 70, project mU 999 or something similar on the front and back

SlowTeg

If the OP is on staggered tires I 100% agree. You should be running same pads front/rear, or you'll overwork the front and have too much nose dive in my experience.

scottdh20

i have only put one really good weekend track event on my dtc70's on blanks...held up great, more brakes than i knew what to do with. after inspection i noticed absolutly no issues after about 2.5hrs of collective track time. also doesnt look like i killed very much pad at all which is a plus

already signed up for a few events this year, plus 3 or 4 more that registration hasnt opened for yet. so we'll see how well they last

imstimpy

I run 255 RS3s on 17x9s at all four corners. The track day prior to this I had square pad compounds and overheated the rears first.

Honestly, I haven't tried a lot of compounds on the S2000. The XP10/XP8 combo came with decent reviews, but apparently aren't the track pads I thought they were. Other than the howling, they are fine on the street. The same could not be said for the PFC97s I ran on my Evo.

imstimpy

BBKs are legal in STR. Finding a BBK that fits within a 17x9+63 is a problem. I have some ideas though...

SlowTeg

Ahh that changes things considerably.. I wasn't sure if you were on a square or staggered tire setup. With a 255 square setup, a BBK is a must imo. Unless you just plan on putzing for most sessions and trying to run a few hot laps. While you could run a higher temp pad and it might help a little, the problem is the brakes are just undersized for the amount of grip you have.

Regarding wheels, there are a few 17x9 +63 wheels that fit w/o spacers. TSW Nurbugings, supposedly new Koseis, are all I can think of off the top of my head. Not too many, but there are a few affordable options.

thomsbrain

Accord caliper and racingbrake's 2-piece rotor for the S2K/Accord combo might be an option?

GEARHEAD

When talking to Cobalt Friction a while back, they mentioned that they use 80 ksi material for backing plates where most mfg's are using 35-45 ksi material.
I raced on stock calipers/rotors for 10+ years and never bent a Cobalt backing plate. This includes running with 350+ whp and Hoosier A6's and running track record times. I have run my front Cobalt XR-2 pads to within 1mm of friction material. I would occasionally get chunks of friction material breaking off at the corners when running very thin and would crack rotors frequently but never had a backing plate permanently deform. I have seen Carbotechs with bent backing plates at the track. I eventually upgraded to an AP Racing/Urge Design front brake kit to reduce pad wear and rotor cracking but stock brakes can handle an STR setup on the track with appropriate pads. My guess is that the pad compound used has a relatively low coefficient of friction and required lots of force. The high force combined with long/hard braking zones led to enough heat to weaken the backing plates (or substantially lower the modulus). The high piston force acting on the weak backing plates caused the deformation.
My suggestion is to use a pad compound with higher friction coefficient and higher thermal capacity. XR-1, XR-2, DTC-70, etc.

What were your greatest speed deltas at this track?