[evanescent03]

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**Edit** seems like the biggest thing I could've done better is remove the brake duct covers. I just assumed the CS was set up front the factory ... oops.

So. Did a day of HPDE and blew through the stock pads (steel), damaged the rotors. Looks like I’ll need a new set of front rotors/pads. Rears look pretty good. Car otherwise drove great. Fast, stopped great, balanced. Track mode and aggressive settings except comfort chassis. Maybe the leftover nannies contributed to accelerated wear? Top speed ~150mph. About 90*F ambient temp in intermediate group at Summit Point Motorsports track, WV.

If you’re going to drive the the car hard, look at more robust pads. Great experience otherwise but sad to rip through pads so fast. It might be slightly on me because I also burned up pads (while damaging rotors) on 718 gt4, GR86, SS1LE.

Have fun out there! Now to find some replacements for the street.

[Gottagofast]

Did remove the cooling duct covers?

[beamlord]

Regardless of the event, this is unusual. There's two ways you can completely wear down your pads to bare metal (since you mentioned damage to rotors):
- you're driving at a gt4 level endurance race
- complete opposite, your braking/racing needs a lot of improvement
(Not to sound like an expert, my own braking is far from perfect and I am constantly working on that).
Or your pads were already half-way through? The wear accelerates exponentially due to reduced mass. Hence always better to use a separate fresh set of pads before each full-day event.

[forcefed]

Originally Posted by evanescent03

It might be slightly on me because I also burned up pads (while damaging rotors) on 718 gt4, GR86, SS1LE.

So you didn't learn anything from your previous 3 experiences?

[BEAR-AvHistory]

What was the mileage on the pads before you started the day?

[Needsdecaf]

Originally Posted by evanescent03

So. Did a day of HPDE and blew through the stock pads (steel), damaged the rotors. Looks like I’ll need a new set of front rotors/pads. Rears look pretty good. Car otherwise drove great. Fast, stopped great, balanced. Track mode and aggressive settings except comfort chassis. Maybe the leftover nannies contributed to accelerated wear? Top speed ~150mph. About 90*F ambient temp in intermediate group at Summit Point Motorsports track, WV.

If you’re going to drive the the car hard, look at more robust pads. Great experience otherwise but sad to rip through pads so fast. It might be slightly on me because I also burned up pads (while damaging rotors) on 718 gt4, GR86, SS1LE.

Have fun out there! Now to find some replacements for the street.

Apex vaporized a set of pads in 10 taxi laps on the Ring. Switching to endless they got 100. They then added additional cooling and got over 170.

Change pads, open the ducts, add additional cooling.

[BMWRacer523]

This doesn't track (pardon the pun). I'm quite familiar with SP Main and you shouldn't be destroying front brakes there, especially in the intermediate group. As someone else asked, did you remove the vent covers? How much pad depth did you have prior to the event? I've got about 4 track days on a set of OEM pads/rotors and they still have a couple days on them. I did need to replace the rear pads before the last event.

[evanescent03]

Thanks for the input guys!

Bottom line ... new car, new track, always lessons to be learned - the brake duct covers seems like something I definitely should've removed prior to the track day! I didn't do my due-diligence. hopefully someone can learn from my mistakes. I will say that there was ZERO fade at any point which would have triggered me to think something was going on with overheating. i've had nannies kick on with other cars and overheat breaks and inducing fade... made me investigate and turn stuff off. the 3CS was running so well i didn't suspect anything amiss.

Originally Posted by Gottagofast

Did remove the cooling duct covers?

Sure didn't. I didn't expect to do a whole weekend but figured i could get through a day "as-is" ... oops. I'm guessing the brake ducts would've helped a lot.

Originally Posted by beamlord

Regardless of the event, this is unusual. There's two ways you can completely wear down your pads to bare metal (since you mentioned damage to rotors):
- you're driving at a gt4 level endurance race
- complete opposite, your braking/racing needs a lot of improvement
(Not to sound like an expert, my own braking is far from perfect and I am constantly working on that).
Or your pads were already half-way through? The wear accelerates exponentially due to reduced mass. Hence always better to use a separate fresh set of pads before each full-day event.

1 of 4 front pads was down to the metal (drivers side interior pad). the other 3 were down to about 3mm. rears are all about 4-5mm. i'm thinking the lack of opening ducts along with that front left being a hotter corner (as indicated by tire wear) was a vicious cycle in destroying the pads.

I'm definitely not a GT4 level guy. But i don't think i'm the complete opposite either. I too realize I have a lot to learn. Are you aware of certain braking styles that you think would cause this? I believe folks who drag the brakes and have an excessively long braking zone tend to inject more heat into the system. a compressed braking zone, afaik, actually helps reduce brake wear.

Originally Posted by forcefed

So you didn't learn anything from your previous 3 experiences?

I've asked a ton of people at the track (drivers, race mechanics/"brake guys", etc) and have had a hard time pinning down the answer. And everyone I've talked to has been a lot more helpful than you, thankfully. thanks for the contribution

Originally Posted by BEAR-AvHistory

What was the mileage on the pads before you started the day?

about 2,000 miles of normal street driving.

Originally Posted by Needsdecaf

Apex vaporized a set of pads in 10 taxi laps on the Ring. Switching to endless they got 100. They then added additional cooling and got over 170.

Change pads, open the ducts, add additional cooling.

the ducts alone i'm guessing would've helped a lot, wish i would've RTFM on that one. ambient temps were ~90* but not 110* like I encountered at thunderhill in the past.

Originally Posted by BMWRacer523

This doesn't track (pardon the pun). I'm quite familiar with SP Main and you shouldn't be destroying front brakes there, especially in the intermediate group. As someone else asked, did you remove the vent covers? How much pad depth did you have prior to the event? I've got about 4 track days on a set of OEM pads/rotors and they still have a couple days on them. I did need to replace the rear pads before the last event.

nailed the pun! vent covers are definitely the big thing I should've thought of. kinda crazy to think that would make such a big difference but honestly, it probably would've been super helpful. side note that i'm sure you're aware of .. if you're replacing the rears before the fronts, that probably means the nannies are kicking in and wearing them down, yeah? which settings are you running? I enjoyed SP! I haven't ever driven there although I did run Jefferson about 13 years ago. I was hitting 140s-150 at the end of the straight and i think my best time was 1:23.99 per Garmin. i'm not hot-shoe so it takes me a while to learn a new track. I'll be going there more often in the coming years because i'll be moving closer.

[SFVM3]

Good rule of thumb, you should never start a track event with less than 6 mm and I check after day 1 of a 2 day event and swap as needed--I always have a new or 6 mm+ backup set going into a weekend.

If they make Ferodo DS 2500 or DS 1.11 for these cars they are a very reliable and effective pad with predictable wear in my experience--DS 1.11 are next level stopping power/initial bite even cold and last 2-3x as long.

[beamlord]

Originally Posted by evanescent03

Thanks for the input guys!


1 of 4 front pads was down to the metal (drivers side interior pad). the other 3 were down to about 3mm. rears are all about 4-5mm. i'm thinking the lack of opening ducts along with that front left being a hotter corner (as indicated by tire wear) was a vicious cycle in destroying the pads.

I'm definitely not a GT4 level guy. But i don't think i'm the complete opposite either. I too realize I have a lot to learn. Are you aware of certain braking styles that you think would cause this? I believe folks who drag the brakes and have an excessively long braking zone tend to inject more heat into the system. a compressed braking zone, afaik, actually helps reduce brake wear.

While opening the brake ducts would definitely be better, I don't believe it would dramatically change the wear, maybe by 1-2 mm overall.

As for braking, I learned there is a WORLD of difference between a professional driver and amateurs in that. Someone mentioned here already, that Apex rental took 10 laps (Nordschleife, mind you, i.e. 200 Km) to wear down stock pads on their m3 - well, the guy who drove those laps is a professional driver who knows exactly how to minimize brake wear and optimize momentum and speed through corners.
I am certain that an amateur can destroy the pads in under 5 laps.

While braking style and errors are individual, some are quite common.
My own problem is that I often have to do corrective braking after initial braking before corner, because the initial braking was not enough i.e. I tried to keep more speed than necessary ("greedy"), and midcorner realize the entry was too fast. That is a very common mistake. Have gotten better at it recently.

Others include brake dragging as you mentioned.

[BMWRacer523]

Originally Posted by beamlord

My own problem is that I often have to do corrective braking after initial braking before corner, because the initial braking was not enough i.e. I tried to keep more speed than necessary ("greedy"), and midcorner realize the entry was too fast.

This is more of a case of not timing the braking correctly. Very hard to do especially as you get faster. As Ross Bentley says, timing and release of brakes is what separates pros from the amateurs.

[BMWRacer523]

Originally Posted by evanescent03

side note that i'm sure you're aware of .. if you're replacing the rears before the fronts, that probably means the nannies are kicking in and wearing them down, yeah? which settings are you running? I enjoyed SP! I haven't ever driven there although I did run Jefferson about 13 years ago. I was hitting 140s-150 at the end of the straight and i think my best time was 1:23.99 per Garmin. i'm not hot-shoe so it takes me a while to learn a new track. I'll be going there more often in the coming years because i'll be moving closer.

MDM 4wd Sport. So yeah some nannies are still on. Rears needed to be replaced after 6000 miles, 6 track days.

[beamlord]

Originally Posted by BMWRacer523

This is more of a case of not timing the braking correctly. Very hard to do especially as you get faster. As Ross Bentley says, timing and release of brakes is what separates pros from the amateurs.

Well said, exactly my issue, I release brakes early, unconsciously afraid to lose too much speed (losing even more eventually, because of corrective braking).

[Jims M3]

I noticed the brake ducts were blocked on the M4 from the factory when I installed my racing studs.

[CMW33]

Doesn't stability control often contribute to increased brake pad wear since it uses wheel-specific braking?

[Needsdecaf]

Originally Posted by CMW33

Doesn't stability control often contribute to increased brake pad wear since it uses wheel-specific braking?

That would account for increased rear pad wear, yes.

[BEAR-AvHistory]

Any idea why they are blocked from the factory?

[Needsdecaf]

Originally Posted by BEAR-AvHistory

Any idea why they are blocked from the factory?

To prevent debris from hitting the calipers and rotors when the cooling is not needed. Also for "approval-related" reasons. Which I would guess means they add drag, which changes the fuel economy rating.