imstimpy

We swapped back and forth through maybe two sessions. It was a lot of fun and I should have some great video. I regret that I didn't get a chance to go talk to them.

I have a first quarter 2016 braking update. I just finished a two day event at TWS this weekend, logging 360 track miles and a 50 minute finale session. I'm happy to report that the brakes took it all and I am extremely satisfied with the state of my brakes. I have Motul RBF600 fluid and, though the feel is fantastic through any session, I do have tiny bubbles that bleed from the caliper after each track day. I may explore other fluids to see if the characteristic goes away. It takes no more than 10 minutes to bleed with a Power Bleeder so it isn't the end of the world.

At this point I'm at eight track days on the StopTechs and seven track days on the URGE rotors. My front XR2s are also at eight days and have 1/2 to 2/3 life. I retired my rear XP8s three track days ago; they were down to 1/8" to 3/16" and crumbling slightly. I didn't want to chance it given I was driving to the event some two hours from home; I'll bet I could nurse another two days out of them, though. I replaced the rear pads with 13mm XR3s (down from 15mm to fit the URGE rotors); they have similar feel but are harsher on the rotors. I'll post photos of everything when I do a pad swap later this week.

Retired XP8s, after my 01/2016 track day:

TwoRs

Thanks for the write up!

andrewhake

Thanks for the write up! Definitely plan on trying out the urge rear setup now, I am curious how the different rear rotors may effect front wear rates. I would definitely try out some other fluid than the RBF600. Have had quite a few friends move from RBF600 to Project µ, Endless, or Castrol SRF fluid and be much happier.

Urge

andrewhake, AP Racing Radical R4 is up there in that list.
http://www.apracing.com/products/rac...id-cp6005.aspx

imstimpy, it seams your fronts are lasting longer than typical? If you agree, could you ballpark the improvement in wear?
50 min tracking session at TWS is quite intense, how would your non vented rear set up compare.

URGE

imstimpy

Save for only a single track day, I didn't have a chance to evaluate just the front upgrade or just the rear upgrade. My reference is a basic pad and rotor upgrade versus the full upgrades I have today. Wear is considerably improved but I don't know what percentage is due to the front or the rear. The best I can do is summarize what measurable wear I have on my upgrades over eight track days.

At eight track days on the front pads, the XR2s have worn from 18mm to 15-16mm. With the track days on XR2s, and autocross runs on StopTech Street pads, the rotors are just showing micro cracks but are otherwise in great condition. As you can see in the photo, there is a channel near the inner edge on both rotors that I cannot explain.



At three track days on the rear pads, they have worn from 13mm to 11-11.5mm. The amount of wear is disproportionate to the front. I don't know if the "accelerated" wear is due to a more abrasive XR3 compound, the durability of the Flow rotor material, or the demands or thermal capacity of the rear braking system. It could be due to suboptimal conditions (cold) on the track pads due to driving to and from two track days and an autocross. The Flow rotors and XP8s wore reasonably well over four track days previously, with minor pad smearing that cleared immediately with my street setup.



I'm now back to StopTech Street and Ferodo DS2500 pads. I'll see if I can reset the wear of the Flow rotors to gain a better idea of wear in optimal conditions. The rear wear could be normal and, instead, the front is abnormal with great pad to rotor compatibility. All my track days at TWS have been with full upgrades. I baked a half set of DS2500s when I ran a stock-like braking system at Harris Hill Road, then a full set of XP10s and 50% of my rear XP8s when I ran the same braking system at CotA. I believe I also had to turn the rear rotors after the following trip to CotA with StopTechs fronts and solid rears. With both front and rear upgrades, I haven't had the need to turn any rotors.

No.Division

*Off Topic* Info on your string alignment setup, specifically the stands mounted to the hubs. Thanks!

youcandoitall

Imstimpy, thanks for posting your review. Do you keep the rear pad retainer clips (they'll need to be shaved down)? or running without them?

imstimpy

Running without.

turbo8765

Does the OP have any relationship w Patrick or Urge? Did you pay retail for the urge rotors mentioned in the review?

imstimpy

A relationship? Yeah, I have a customer/vendor relationship with Patrick whereby I've purchased parts a few times. No, I didn't pay retail; I purchased at the introductory pricing that was extended to everybody during the product launch.

End of 2016/early 2017 update:
I have not replaced nor resurfaced neither front nor rear rotors. The fronts are at eighteen (18) track days and the Flow rotors are at fifteen (15) track days. The fronts continue to show micro cracks but nothing to be concerned about. The rears clean up after scuffing with street pads.

Back in July 2016 the rear Cobalt XR3 pads exposed rivets at about half life and lightly scuffed my Flow rotors. They netted about half the longevity of the Carbotech XP8s (that went through hell). Though the front XR2s still had some life left in them, I chose to retire the XR2/XR3 setup in favor of the "magic bullet" pads: Raybestos ST43/ST42.



Due to lead times on a custom depth rear pad, I ordered full depth ST42s for the rear and used a manual mill to take out 1.5mm of pad material. Though I don't expect many to have access to a manual mill, I can say the process was super easy and very low effort. I took the ST43/ST42 back to Texas World Speeday. Their first (and only) track day had good balance, but all my braking points were too early due to the aggressive nature of the pads. I could certainly push the braking zone deeper, but the aggressive pads created difficulty in threshold braking. I lost confidence in the brakes and my cornering speeds suffered in inconsistency. I might suspect better results on race tire compounds but they are too much for even the grippiest street tires. I pulled my front XR2s and rear XP8s out of retirement to eek through the second day. Despite the fronts being at 10mm and the rears being at 3-4mm, I was able to run a full day with zero braking issues.

I purchased yet another set of pads, this time to replace a compound choice I didn't care for. This time I went with Carbotech XP10s and XP8s. Though the compound was the same as my initial foray into track pads, my braking hardware was all different. I was able to order a custom depth XP8 pad to fit the Flow rotors, ordering 13.5mm instead of the typical 15mm (they dropped right in). I'm happy to say my first trip to MSR-Houston went without a hitch. The brakes were on point: balance, bite, and modulation were all just right. Pad cost was much cheaper than the re-equipping with the Cobalts and, furthermore, I anticipate the Carbotechs to last longer. I think I've found my sweep spot with a relatively "heavy" S2000 and street tires.

A little Good Morning car warming before the track event:


New Carbotech XP8s vs super used (but still usable) Carbotech XP8s vs half-used (but not usable) Cobalt XR3s:


Post-MSR-Houston track day on Carbotech XP10s and XP8s: