Vampire

How long do 911 Carrera brake pads last if used in track conditions?

Bill Gregory

Stock pads don't stand up too well at drivers education. The variable is how you brake, of course. One person with new street pads might get through 2 days of DE, while another might go many more DE days. Here's an article I wrote for our PCA region's magazine on brake pads, perhaps it will provide some additional information:

When you first start drivers education, your stock brake pads are OK, however, you'll find shortly that combined street and drivers ed events leads to a significantly shortened pad life. As an upgrade, there are several brands (Hawk, Performance Friction, and others) of high performance street pads that can be used for both street and track. Pagid, Ferodo, Peformance Friction, Hawk, and others, make race pads which can be used as a combination street/track pad too. Track pads do tend to be noisier (can you say "squeeeel") and produce more brake dust than some of the street-only pads. After this, you move into pads that are really only for the track, as they have a specific heat range that they operate in - that means they don't work well on the street where your rotors are usually cold (as compared to being heated up at the track). Of course you can always run street pads on the street and swap them out for your drivers ed event. When you get new pads, make sure you understand if any specific break-in procedure is needed. Some, like Performance Friction, don't need any break-in done, and others, like Pagid, definitely do. If the pads need breaking in, and you don't do this, you can experience "green fade" where, as your pads heat up for the first time, binders and glue in the pad material boil out, turning to liquid on the rotor. Firm brake application without commensurate slowing down - yikes! Also, if you find yourself attending drivers ed events with some regularity, it doesn't hurt to bring an extra set of your favorite pads with you to the track, in the event you wear your existing pads down to 40%-50% of the original thickness and need to replace them.

Required statement: Written by Bill Gregory for the "Challenge", monthly publication of the Connecticut Valley Region, Porsche Club of America.

Chris Bennet

The only time I really kept records I got 14 track/person days on the rear and 17 on the front using Pagid Orange on my '86 Carrera.
-Chris

[ 31-05-2001: Message edited by: Chris Bennet ]

Chris in Detroit

As a contrast to Chris' experience, I'm literally on-track (groan) to get about 10 track/person days out of both front and rear Pagid Orange on a 993 Carrera. However, I run DOT-R compound tires, so am maybe braking harder than his 86 Carrera - hence more wear ? Lots of variables

In the past I have had JUST one day out of a set of aftermarket stock pads (there is a lesson there) and a friend got just a couple of weekends from a set of aftermarket stock pads.

There is a lesson there - get Porsche OEM pads, OR, if seriously tracking the car a set of Pagid or Hawks etc. are probably worth it .....

Adam Richman

I can't respond to the original post but I can comment to running OE pads, Hawk HP+ pads and Hawk Blues on a 944S at VIR, Roebling Road and CMP.

I can say that there wasn't that much of a difference in the stopping power of the HP+ over the OE's (maybe a hair) but the +'s held up longer (8 track days and they were at 50% and CMP if you know it, does a dance on anybody's brake system).

Now going to the Hawk Blues was a totally different story. Once they bed - and that has been my biggest difficulty with Hawks - they are friggin amazing. I moved my brake zone up 2 markers in most spots over the HP+ or OE's.

Other contributing factors. I run Super Blue, SS Lines, swap pads AND rotors at the track as well as partially bleed the calipers (read: compress piston w/ speed bleeder open) now in conjunction with the Blues. I am told that it can make a considerable difference in not transferring the friction material from one pad to the next regardless of its compound. This stuff I've heard so I don't say it as if it is an absolute truth. I was also told that the same may be accomplished by using emory cloth on the rotor surface when you swap pads if you don't want to go the route I do.

Billy, I realize your post was directed to the 911 but I figure brakes is brakes. Regardless, sorry for the interjection if it is unwanted. I would also echo what Chris in Detroit is saying that there are a ton of variables (tire compound, how long you stay on the brakes, track type, ducted air to the hats, trail braking - don't know if you guys do that - etc . . .)

Take care

addictionms

One other variable is which track, here in San Jose, we run four different tracks, some are high speed like Thunderhill and these are easy on pads, others are low speed, like Buttonwillows or Sears Point which are hard on pads.

Plus, I am convinced that left foot braking is harder on pads, faster on the track, but harder on the pads. This is because you can be on the brakes and the gas at the same time to balance the car, thus you are wearing the pads more.

Adam Richman

Jim, I have noticed something a bit weird and perhaps you can corroborate. My street pads (driven almost entirely on the street) wear identically inner vs. outer. Conversely, the HP+ which I did 8 track days with, are significantly worn worse (thinner) on the outer pad. My initial thought was that it was just the nature of the brake system. I then compared them to the OE's and derived a different hypothesis. I trail brake the car anywhere from a fair to moderate amount. I am wondering if the loading of the outside of the car is translating to loading the outside rotor and subsequently the outside pad of the outside rotor. This make sense to you or anyone else or am I seeing something occurring for a different reason?

Adam

addictionms

I can't say I have actually noticed uneven brake wear, that is not to say it is not there, I just never noticed it.

It is possible that on the street there is more time between appliction and a dragging piston has less of an effect?

Cookie Porsche

Adam and Others, I'm not sure this is how to reply to a sub-thread, but here goes. The reason your outside pad wears more than the inner on the track is heat. Your car scoops cool air onto the inside of the disc when driving, thus the pad wears less. On the street the heat is minimal thus you achieve even wear. Hope this helps. Regards Tom.

Adam Richman

Thanks, that makes sense. Do you know if ducting reduces that outer pad wear? Edit: in relation to the inner pad (balance out the wear).

[ 04-06-2001: Message edited by: Adam Richman ]

TT Gasman

At the end of my last DE (also my first)the instructor thought he heard my pads making noise ( I thought it might have ben the car behind). I pulled the wheels and there is a lot of meat still left.The car shows no such symptoms during daily driving over the last month. My question, can you wear out a set of stock pads after just one DE??

Adam Richman

Quasi-related. I tracked my Acura (CL-S=3505 lbs w/out driver and a 61/39 weight distribution). I destroyed a set of pads Carolina Motorsports Park first time out. Replaced pads with Porterfield Carbon Kevlar variety (NSX rears and cut for the front of my car) and in two events, destroyed rotors and pads. Needless to say, that's a much different car than yours in oh so many ways but I would assume you can do as much damage as your driving style allows at one event.