_rocket

According to this thread https://rennlist.com/forums/997-gt2-...r-997-gt2.html, not only you have to get narrow annulus (8004) pad, you'd still have to grind off the small metal lip at the inner edge of the pad.

mikymu

First I want to thanks those of you that helped with your advice on the steel rotor swap. Can't do it without referencing this forum for help

I hope Brembo and other aftermarket rotors fit better than Cup rotor. I don't have experience with them so I can't comment if they fit better or not

Yes, the write up took almost as long as the mod itself. Glad I don't need sleep lol

Yes, the house next door to me is forsale and they are looking for a Ferrari DIY nut

I spoke with couple Porsche race shop and they told me not to bother with SS brake line which I have on my M3 and I like the improve feel. apparently the SS brake line may crack under stress?

mikymu

I thought wrong if the 997 Cup cars are narrow body. The parts number I got was directly from Porsche motorsports and I don't think they are 993 parts

I don't think you can put a spacer behind the rotor. It has very exact groove and barley sits right. I don't think it's bad to grind down the brake pads a bid to fit. A-lot of race shop do that to customize their race cars

GTEE3

Re: Bleeding brakes,
a good idea is to cycle the ABS a few times before bleeding, (by turning the key on/off...not start)
and when spreading the pads (caliper pistons), take your reservoir cap off and cover with rags, or just have less fluid in the reservoir.

911/Q45

Great post! Loctite on rotor to hat bolts?

mikymu

QUOTE=GTEE3;7085637]Re: Bleeding brakes,
a good idea is to cycle the ABS a few times before bleeding, (by turning the key on/off...not start)
and when spreading the pads (caliper pistons), take your reservoir cap off and cover with rags, or just have less fluid in the reservoir.[/QUOTE]

yes, very good idea to do the above

I use anti-seize on the two small 10 mm hots for the rotor hat - I think it is Loctite

Atgani

To the OP, how many miles had you done in the car prior to your first track day ? Porsche, Pagid and SGL have recognised an issue they've termed "green fade" (this can affect ALL brake pads, but seems to have been a real issue with PCCBs.

It appears to occurr due to a lack of proper bedding in of new brake pads. The result is what you experienced, that being pretty much total brake fade with little or no retardation.

My guess is you "cooked" your PCCB pads prior to heat cycling them correctly. Once they have been incorrectly heat cycled (too hot/too soon) they cannot be used successfully. The ONLY cure is to fit new pads and bed them in correctly.

I've had this issue three times once on my MK1 996 GT3 using the standard pads, and twice on a 996 GT2, once with Pagid RS29s and once with the standard P90 Pagid compound pads.

I quote verbatim from Rennsports website :

To prevent the phenomenon known as "green fade", all brake pads must be "bedded in" before you will achieve the maximum friction that your pads are capable of. Green fade occurs when the pad material is overheated before it has a chance to cure. The binders and glues that are used to mold the material together are boiled out and turns to liquid where the pad meets the rotor surface. This is a very scary situation since you get very little warning and the pedal remains firm and high. Bedding the brake pads allows the working surface of the pad to ‘cure’ so that the boiling out process happens in the first few heating cycles. This process occurs continuously through the life of the pad, but the effect is most obvious at first.

Each brake pad manufacturer has their own specific instructions on how to bed their pads properly. When you install new pads, you should gently warm the pad up by making 25 to 30 stops, gradually increasing the brake pressure, but never getting them really hot. This takes bit of practice to perform properly. After making those series of stops, you then make a good hard stop from 110 or so mph, down to about 30 mph and park the car without holding any pressure on the pedal. Let the brakes cool enough that the wheels are cool to the touch. At this time, you should have "cured" the pad material so that it creates its highest coefficient of friction

HTH

crispenigl

Amazing post... wow

Could you just start with steel rotors instead?

GTEE3

Great job documenting the process, and doing the research!
thanks

mikymu

Green fade is a very good possibility since my RS had 6K miles when I bought it and only seen track once. Thanks for the advice on bedding technique. I do something similar. I will play with my PCCB next year and try out couple brake pads options

I wish i knew better before buying my RS. If I were to order the 2010 RS, I may get the steel rotors instead ... or maybe PCCB then convert to steel rotors one more time for the team lol

sws1

I'm not sure if I experienced green fade, but I did notice when I tracked it, after a few laps, I lost alot of the bite. Took alot more pressure to get car to stop which was not confidence inspiring.

I also noticed that when driving home (and for next few weeks of street driving), the bit was gone on the brakes. Interestingly enough, after 2-3 months of street driving, the initial bite came back.

malmasri

Thanks for sharing your experience with us.... it clearly takes a certain talent to do what you have done..I have had a simillar experience with mine on the 1st track day ever in it...break pedal down nothing happens..fortunately it was not DE...but open track so I kept driving relatively slow and breaking not as hard for several laps and I guess that must have been enough to seat the pads appropriately.. since then I had 5 track days and the breaks felt no differnt at the end of each session that at the begining ..xcpt that I wore the rear pads and had to replace them, with fronts still at half life.
Top notch post....

savyboy

LOL, you are too funny!

Tim Kay

Say you do have ‘green fade’ on a set of pads less than 2000 miles street, are the pads ruined for all intense track purposes or can they ‘come back’ as replied by sws1 above?

Green fade does not affect the rotor does it?

Atgani

Green fade should have no effect on the rotors at all. In my experience once pads have been incorrectly bedded in they are not useable and will NOT "come back".

My recent experience after not bedding in the front pads on my Mk 1 GT3 showed the pads to have heat cracks to the wearing surfaces, this was after less than 200 ROAD miles. The heat cracks will be due to excessive heat being genereated within the friction material prior to the pads being properly bedded in.

When this happens it appears the pads glaze up, and rather than provide the C of F the manufacturer intended, all they produce is heat ! This vicious circle in turn produces less friction but generates more heat. The net result is blued discs and friction material that has little or none of the manufacturers intended co-efficient of friction.

When this happened to me previously, I tried removing the glazed face of the pad with coarse emery cloth. On closer inspection the center of the pad had cracked and it's properties were totally didfferent to that of the surrounding material. I binned them

Picture of "cooked" Pagid pad prior to my trying to de-glaze it.