vette ruminator

Last year I tracked my ZR1 at Autobahn CC in IL (3.5 miles, 21 turns) and Road America 10 days total. I used stock PS2s and was happy to just put gas in and go. I did change the camber to get more life out of the tires after my first set of PS2s wore out the outer tread way too fast with stock camber.

Last year, I got about 20 sessions 20-30 min each out of a set of pads, and I ran mostly in PTM 3. That was with 10 mm starting thickness on the pads and assuming that at about 5 mm they are close to done for track use.

I put 4 new pads on for the start of this season and did a 2 day, 8 20-30 min session weekend with NASA at Autobahn CC in cold (38 degrees in the morning) April weather, and I used the PS2s. on 5/7 I ran 2.5 30 min sessions in a downpour on the MPSCs, babying the car to keep it on track and I'm sure I didn't use much pad, but I did use only PTM 1 as I had the cup tires on and I have experienced the ol' kissing the guardrail in my Z06 in the rain; that wasn't gonna happen to my ZR1.

On 6/11 I finally got a chance to use the Pilot Sport Cup zero pressures in great 85 degree conditions and the grip was great for a day of 6 hard 20 minute sessions. My time actually dropped by about 6 seconds on the 3.5 mile Autobahn course, as I clearly had higher speeds everywhere on the track, with increased confidence, and I switched to PTM 4.

After those 14 dry sessions and 2.5 wet sessions I was switching my MPSCs from side to side for more even wear and I took a look at the brakes before my next event on 6/18. The rears had plenty of pad left for at least one more day (at least 6 mm inner and outer pads), and my front outer pads also were passable, at 5 mm. The front inner pads, however, were dangerously low at 3 mm and there were some spots on the edge that were already starting to crumble off and expose the backing plate. The "change brake pad" message on the DIC was nowhere to be found even though plenty of the brass rivets were exposed. I basically got only 14 good sessions out of my inner front pads.

I put in some spare front inner pads with 5 mm left, and on 6/18 did another 3 sessions 30 min each on PTM 4, replaced the inner pads again with more 5 mm spares as the inner fronts had worn down to 4 mm, and made a serious effort not to over-brake. I did 2 more 30 min sessions at 8-9/10s and called it a day. Time to order new pads.

How many sessions are you HPDEers getting out of a set of pads? Do you find the inner front pads wear out much faster than rest? A simple, bolt-on brake duct cooling system would do a world of good here. At what thickness are you guys changing the pads? Do you ever flip the pads right to left to wear more evenly by changing the leading edge of the pad, or by the time they start to taper are they close to done?

Ian and others who have switched to R-comps like MPSCs, are you finding your brake life is much reduced from the higher speeds? When do you start weighing the rotors and checking the rotor thickness?

Just trying to optimize our pricey brake setup, but having a blast ...

Noel

isnider

I am getting roughly 3 track weekends out of front pads. Rear pads I am getting 5 weekends. I was initially concerned about burnishing new front pads with the old rear pads but it is not an issue. One of the things that really improved for me was hard braking with the MPSC. I never engage ABS under hard braking now and I am convinced I have picked up 5-6 seconds per lap over the PS2's.

BTW, I wouldn't worry about the brass rivets. I run the pads to a micron before the the black plastic sensor would come in contact with the rotor. You might see brass residue on the rotor but that quickly disappears after you install new pads.

I haven't weighed my rotors yet, they still look the same as the day th car was new. My gues is may maybe after 10 sets of pads, the rotors need to be weighed.

BTW, the best price I have found on the pads is Amazon.com (free shipping too)

Ian

vette ruminator

How many sessions would you say you do in 3 track weekends? I'm trying to figure out whether 14 sessions from my inner front pads is reasonable or not. At what thickness do you feel the pads need to be changed?

topmover

I honestly dont think there is alot of guys who track these cars and I think some who do(like me some of the time) dont like to post about it a lot for fear that GM is watching.

If I recall JVP had indicated last year that he was told by someone reliable that there is no issue with running the pads down into the rivets. Since then I have been going down into the rivets(although it freaks me out a bit thinking about it) and it does not appear to be an issue. Ian has confirmed that he does this as well.

I think uneven pad wear can be caused by a number of issues from driving style, alinement, track, nanny setting, wheel deflection etc. My ZR wears pretty evenly while on my Z06(AP's) I have to flip the pads due to uneven wear and pad taper.

I have noticed that at the two Summit Point Tracks I run my wear front to back is similar but as I've started to run VIR more with its longer straights I'm getting more front wear.

I personally consider a track day 4 20-25 minute sessions. For my first 10-15 track days with my ZR I averaged 266 minutes which is what......12 sessions/3 days? Maybe because I run VIR more or maybe because I have A6's on much of the time or maybe because my rotors are getting shot I'm getting less pad wear recently.........more like 2-2.5 days.

K B Vettin

look at the Katech front splitter with undertray and brake duct kit. i'm ordering mine soon to help with the same brake pad issue.

http://http://ls1tech.com/forums/cor...pre-order.html.

isnider

That would be 4-5 session per day at 20-30 minutes per session (all depends on which group is running the event)

Ian

vette ruminator

Any others? JVP? 911/Q45? Those who post about their track experience likely have needed pad change at some point...

911/Q45

I've gone through lots of pads, but can't quantify how much use was involved. Some days are busy and I spend most of my time in other people's cars. Some tracks are harder on brakes than others. I probably don't want to know on some level. I'm having a good time with the car and change the pads when they get skinny, usually just before the sensors trip.

topmover

I dont messure my pads either, I run them down till they get fairly skinny and depending on what my track plans are I will make my change based on that. Clearly the expense is a issue for these brakes however for me the biggest PIA is the need to perform the street brandish, my track schedule does not alway line up with the wear rate of the pads.

vette ruminator

All good info; good to have it in one place. I measured some old pads again and on the inner pads the thickness of the attached connector for the worthless "replace pads" sensor is just under 4 mm so that's about the limit of the inner pads; I'd use that on the street only.

Does anyone find the front inner pads wear much more than the outer pads? It would make sense based on the higher heat inside the wheel well but just seeing if that is common issue...

911/Q45

My fronts wear evenly, no taper or inner/outer disparity.

vette ruminator

Anybody else notice excessive front inner pad wear compared to the outside?

JeremyGSU

I don't have a ZR1 but I've seen my inner pads wear more than the outers before on my C5 Z06 running stock calipers and XP12 front pads and ducting. Not sure what causes it. Perhaps the outer pads still get more airflow and less heat?