1st brake pad swap on 05 GT

[RichV]

Just swapped all 4 corners. Had some strange uneven wear.

All 4 corners are the PowerStop D/S rotors, pads were the PowerStop brand. Whatever comes with the kit.

They actually did OK on the track, even with a premium GT that tips the scales at 3700 with me in it. Didn't start getting fade until the pads were down to the last few bits. They lasted a whole 4 track days, plus 4K miles of street use. They were new when I bough the 05 early in the year.

Got some HPS pads for the front and some generic ceramics for the rear. Kept the PowerSlot rotors for now. When I took the front pads off, the outer pad was worn evenly and the inners were all completely pie shaped. About 1/4 of pad at the top, almost nothing at the bottom. Lower piston was out a bit more than the upper. Rears wore relatively even, both driver sides on front and rear had a little less pad than the passenger sides.

Anyway, what's you guys' experience running open track. Is this normal? Do I just need to rotate inner/outer pads after every track day? Not used to a set of pads burning up in 4 track days. Could get costly.

 

[Norm Peterson]

I wouldn't count on getting too many more than four days out of any pads. You should be inspecting them after each event, and replacing them no later than when they're worn down to 50% thickness (or about 1/4", which some track day groups may require). Pads are called 'consumables' for a reason.

FWIW, I *might* be able to squeeze a sixth day out of a set of XP8 pads with 0.3" remaining on most, but with the LF down to about 0.27" with probably a 5 sessions in class + extended 6th (open) session event coming up next I'm swapping at least the fronts (and stepping up to XP10's while I'm at it). Of the five events already in, one was a totally wet day and another one was not raining but went from wet to dry in terms of track condition.


In general, HPS and street ceramics DO NOT BELONG ON A TRACKED CAR. For an introduction to tracking where you're following a lead car (whose driver/instructor knows what you have) in progressively paced laps, they should be adequate, but don't even think of using them for anything beyond that.


Norm

 

[Sky Render]

Throw those crappy drilled/slotted rotors out in the street and get some solid ones. Drilling and slotting rotors belongs on carbon ceramic systems and hard parkers.

 

[csamsh]

I got five days out of my XP16's, XP20's are going on three and still look pretty solid

 

[RichV]

I'm definitely gonna ditch the drilled and slotted, them more I think of it I bet the slotting is what caused the uneven wear. They're still straight, and still work.

Running in TTD is way different than W2W. No need to get inches from one another. I want a good street friendly pad since my 05 is a dual purpose. A lot of race compounds need a lot of heat which you can't generate going to Burger King. I've run the XP10/XP12, Blues, and DTC70 but that's a different car.

 

[Norm Peterson]

What do you consider "street friendly" in terms of dust and noise? XP8's and HP+ both have adequate cold bite, though the XP8's are far, far kinder to your rotors than the Hawks.


Norm

 

[RichV]

I'll have to check out the XP8s. I went with the HPS because I had some Hawk Bucks from contingency, got the front set for $16 shipped.

Are the XP8 good for front/rear? When I ran CMC1 we ran XP12 on the front and XP10 in the rear.

 

[2Fass240us]

I was getting uneven wear on my pads too. My guess is that the heat cycles eventually altered the way the OE bracket and caliper squeezed the pads.

I HIGHLY recommend cooling and (as others have mentioned) better pads. I eventually switched to Wilwoods with custom brackets and 11+ GT rotors.

 

[RichV]

I was getting uneven wear on my pads too. My guess is that the heat cycles eventually altered the way the OE bracket and caliper squeezed the pads.

I HIGHLY recommend cooling and (as others have mentioned) better pads. I eventually switched to Wilwoods with custom brackets and 11+ GT rotors.

After how much track abuse did the calipers clam shell?

I had a set of 99-04 GT front PBRs on my CMC car for years, I still have them in a box. The aluminum pistons cracked from the heat before the body clam shelled.

 

[Norm Peterson]

Does the taper wear look like any of these?

http://www.brakeandfrontend.com/brake-pad-wear-chart/


Norm

 

[2Fass240us]

After how much track abuse did the calipers clam shell?

I only had 4 events on them. Two of the four were at Carolina Motorsports Park, which is pretty hard on brakes.

EDIT...here are some measurements I took after the 4 events. The low numbers are toward the outside of each pad and the high numbers are toward the inside. Pads 3 and 4 were "outside" when I took them off; I may've been able to get another day by rotating them, but I changed to Wilwoods.

DTC60 thicknesses:
Pad 1: 0.229 - 0.234"
Pad 2: 0.238 - 0.258"
Pad 3: 0.115 - 0.160"
Pad 4: 0.140 - 0.173"

I'm not the original owner and have no idea what kind of use the car saw before me.

 

[cop on my back]

I am curious about pad wear. Can you guys equate "track days' to hours of track time. For me, a track day is a total of 1 hour 30 minutes of at speed and I nearly wore 50% of a new set of Xp 20's on the front.

 

[csamsh]

I am curious about pad wear. Can you guys equate "track days' to hours of track time. For me, a track day is a total of 1 hour 30 minutes of at speed and I nearly wore 50% of a new set of Xp 20's on the front.

wow...are you on a crazily brake intensive track?

 

[cop on my back]

wow...are you on a crazily brake intensive track?

Yes, Pacific Raceways near Seattle is very hard on brakes. For me, turn 2 is 135 mph down to 60 mph very quick and then turn 3 is downhill at 105 mph into a 180 hairpin at 40 mph. It is quite steep.

 

[RichV]

Does the taper wear look like any of these?

http://www.brakeandfrontend.com/brake-pad-wear-chart/


Norm

Yes the tapered wear pic, only it's just the inside pad. Outer pad was fine and even.

1 track day for me is generally 80 minutes, 4-20 minute sessions. But I occasionally go out on a extra session with a student or corner worker. Some days I miss sessions when busy.

Track and driving style have a lot to do with brake wear. Roval tracks seem to be harder on brakes for me as well. PPIR in Colorado Springs is high speed around the oval, the infield is much slower.

 

[2Fass240us]

I am curious about pad wear. Can you guys equate "track days' to hours of track time. For me, a track day is a total of 1 hour 30 minutes of at speed and I nearly wore 50% of a new set of Xp 20's on the front.

The club I normally run with has four 20-minute sessions per day per student group (Green, Yellow, Blue, Red), for a total of 80 minutes per day and 160 minutes per event.

If I only have one student sometimes I can get more than that.

 

[SoundGuyDave]

I am curious about pad wear. Can you guys equate "track days' to hours of track time. For me, a track day is a total of 1 hour 30 minutes of at speed and I nearly wore 50% of a new set of Xp 20's on the front.

I've said before, and I'll say again, that you need to pick your frog and live with the warts. Carbotech pads are easy on the rotors, but wear away quickly. Hawk pads last a LOT longer, but are more aggressive on the rotors.

Any way you cut it, when you hit the brake pedal, you're converting kinetic energy into heat, and something has to give to make that happen. Carbotech and Hawk are just taking different approaches. So, do you want to pay for pads, or pay for rotors?

As a data point, I'm getting roughly 7-8 hours of race-condition service out of Hawk DTC-60s before they're thin enough to start transmitting heat into the caliper; approximately 80% worn. It sounds to me like using the same metric, you're getting ~3 hours out of your pads.

Full disclosure: GT500 14" Brembo calipers, Hawk DTC-60 pads, Girodisc 2-piece rotors, FTBracing spindle ducts, 3" ducting, and fabricated fascia inlets, Motul RBF600 fluid.

 

[cop on my back]

Yea, I have now come to realize that asking factory sized brakes to stop a street car at 3400 lbs at those kind of speeds is just too much. I am going to have to bite the bullet and go with oversized rotors and better calipers.

Better still, I am flipping a house and I think some of the profit will be added to the sale of my current Mustang for a 2013 Boss 302.

 

[2Fass240us]

Yea, I have now come to realize that asking factory sized brakes to stop a street car at 3400 lbs at those kind of speeds is just too much. I am going to have to bite the bullet and go with oversized rotors and better calipers.

Start with brake ducting. Or just buy the Boss.

 

[cop on my back]

Start with brake ducting. Or just buy the Boss.

Already have the ducting, it is quite effective.