Rotor deposit StopTech Floating/Carbotech Panther Plus

[Scin]

I recently installed some StopTech two piece floating rotors after I cracked my previous rotors. I was using Carbotech Panther Plus pads and they had a decent amount of pad left so I did not change the pad with the new rotors. I then bedded them in by doing 10 stops from 60 to 5mph and five more from 80mph to five mph.

The next day I ran the car at California Speedway in the rain. I think I felt brake shudder in my 2nd run, I don't remember if I had it so much in the first run. It seems to only be comming from the front left rotor.

The vibration isn't that bad and its only under very hard braking. I ran another event today and I could still utilize the breaks fully, it was mostly just an annoyance.

My question is what do you think caused the pad deposits, was it the rain? Should I always replace rotors and pads together? Do I need to do more stops to bed them, or perhaps less?

I ordered some Cobalt GT-Sport pads (still in the mail) to replace my Panther Plus pads. What should I do to remove the pad deposit and insure that my new brakes are bedded correctly? Should I just try to put the new pad on and bed them in, or should I try scrubbing with a sponge... or should I get my rotors resurfaced... and will this hurt the life of the rotor?

 

[VintageracerNYC]

Did you replace the OE rotors with these Stoptech two-piece or did you already have aftermarket rotors? Do you like the Stoptechs so far? Why are you going to Cobalt GT's instead of a new set of Panther Plus?

 

[Larry Bastanza]

What is your skill level? How many track days do you have? Are you Open Track, Novice, Intermediate?

The Cobalt pads are LOWER temp them the Panther Plus. If you are leaving deposits with the PP, due to heat, (ask me how I know), going to the GT Sport, is not what you want to do. I went from GT Sport to PP to solve my deposit problems. But....I am not an Open Track Driver, I would say high intermediate. Fuuny too, how as we get better, we use LESS brake. My instructors have said that many times, one of the later steps in increasing your driving skill and lowering lap times is the stop overbraking.

HTH,
LarryB

 

[Scin]

I ran some cheap brembo blanks that were drilled/slotted before switching to the Stoptech two-piece rotors. I didn't have any deposit problems with the cheap rotors and panther pads, however my rotors had tons of small cracks all over them after my 2nd event with them (four days track time).

My primary reason for switching pads is the Panther Plus make so much damn squeeling noise when I drive with them on the street. They seemed to perform well for me otherwise.

Did you replace the OE rotors with these Stoptech two-piece or did you already have aftermarket rotors? Do you like the Stoptechs so far? Why are you going to Cobalt GT's instead of a new set of Panther Plus?

 

[Scin]

I have done four events, so I would say beginner/intermediate. I started in the beginner group yesterday (I like getting instructor time) and later in the day they combined the groups. I was one of the fastest cars on street tires for either group.

I don't think I overheated the pads since the problem started in the rain at California Speedway where the speed was lower. I havn't had any brake fading problems. It just seems that I got an uneven deposit on the rotors (or possibly just the left rotor) somehow.

I realize the Cobalt pads are lower temp, however I don't think I am going to get them above 950F (crosses fingers). My primary reason for switching was brake squeel when driving on the street with the panther plus, and my desire to have a street/track pad.

I do use my brakes less, however I user them harder and I brake later. I am not sure which will get the brakes hotter: using them more often but not as hard, or less often but harder. I am guessing the later, especially when you consider that you will be carrying more speed through the track which means more energy the brakes have absorb.

What rotors were you running when you over heated your GT Sports? Did you have your dust shields removed and did you have any type of upgraded deflectors or brake ducting?

What is your skill level? How many track days do you have? Are you Open Track, Novice, Intermediate?

The Cobalt pads are LOWER temp them the Panther Plus. If you are leaving deposits with the PP, due to heat, (ask me how I know), going to the GT Sport, is not what you want to do. I went from GT Sport to PP to solve my deposit problems. But....I am not an Open Track Driver, I would say high intermediate. Fuuny too, how as we get better, we use LESS brake. My instructors have said that many times, one of the later steps in increasing your driving skill and lowering lap times is the stop overbraking.

HTH,
LarryB

 

[2slow2speed]

If you come off track with hot rotors and then inadvertendly stay on the brakes for a relatively long period of time then it's possible to get pad deposits on the rotors. Either that or you have problems with the pistons on your front caliper on the side that the deposits formed. The deposits could have formed either when you bedded the rotors or at the track, more than likely during the bedding process. BTW: CA Speedway with the infield is brutal on the brakes, comming off the banking into the infield takes quite a bit of braking.

A couple of years back I ruined a set of Stoptech BBK front rotors while having to wait for the track to go back to green at Reno Fernley, the front straight is downhill so I had to stay on the brakes to keep the car from rolling downhill. There was a black flag all which caused the track to be closed, normally I would roll the car back and forth but given that it was downhill and that the person behind me was too close I could not roll the car

 

[Hrant]

I realize the Cobalt pads are lower temp, however I don't think I am going to get them above 950F (crosses fingers). My primary reason for switching was brake squeel when driving on the street with the panther plus, and my desire to have a street/track pad.


With a minor chafing of the corners of each pads (I do about 1/8") and slotted rotors, you will almost eliminate the squeal. Carbotech offers the chaffing if you want but they take about 1/4" at a minimum.

I had the same squealing issue with my first set. Now, I am on my fourth set and the squeal is no more than OEM pads yet still have the advantage of the Panther Plus street/track. YMMV.

 

[GOTTSPD]

With a minor chafing of the corners of each pads (I do about 1/8") and slotted rotors, you will almost eliminate the squeal. Carbotech offers the chaffing if you want but they take about 1/4" at a minimum.

I had the same squealing issue with my first set. Now, I am on my fourth set and the squeal is no more than OEM pads yet still have the advantage of the Panther Plus street/track. YMMV.

The squeal from my Panther Plus pads is pretty annoying. Can you provide us with more detail on this chafing thing you are speaking of?

 

[2slow2speed]

BTW: Stock NSX brakes use floating calipers, so if the pins that are used to hold the caliper on the brackets don't have grease inside the rubber boots or the grease has degraded they can get stuck.

As someone who is getting into tracking, make sure to inspect your equipment frequently before track events.

Track events can put a lot of stress on your car, nsxtasy has written some good articles in past issues of NSXDriver take a look at them if you have a chance.

 

[Hrant]

The squeal from my Panther Plus pads is pretty annoying. Can you provide us with more detail on this chafing thing you are speaking of?

I did Google search for brake pads to show you some pictures. This is a good example: http://www.car-stuff.com/cs_auto/mp-vp/subaru/brake_pads/cs441e2e7a53bd2

I have chafed (filed) the P+ much less than that, as I said about 1/8" max. But I believe the slotted rotors are also a key part of the equations.

Some will immediately pontificate that you are losing maximum pad surface contact by doing this, you would be better off getting a different pad ........ tell them to fly a kite :wink:

 

[GOTTSPD]

Thanks!

 

[Scin]

I regrease the pins every time I change pads.

Any suggestions on what to do with the rotors, should I have them re-surfaced before putting the new pads on?

 

[nsxhk]

I had almost the same brake shudder on my last track event too but only after a few hot laps. It seems to shudder when the brakes get hot but they went back to normal after a cool down lap.

I wonder if it's because I didn't bed in the new rotors with old brake pads?


Henry.

 

[Hrant]

I wonder if it's because I didn't bed in the new rotors with old brake pads?

Henry.

That will do it Henry. What type of rotors and pads are you using?

 

[nsxhk]

Hiya Hrant,

I'm using oem rotors with carbotech pp pads.

Henry.

 

[Hrant]

Definitely need to embed them. And time to upgrade those rotors with slotted ones - they help to cool the rotors as well as keep the pads cleaner :wink:

 

[nsxhk]

I got them slotted by a local machine shop already :tongue:

Henry.

 

[NSXDreamer2]

I have different situation than Henry using PP pads and slotted rotors. Brakes had been "properly" bedded in according to manufacturer's suggestion. rotors and pads seems good at track ever since I swapped the one piece rotor to two piece (Aerorotor). Brake fluid haven't been turn brown after whole track day, despite the pad wears is much higher than before...

Yet, on my drive home, that is, the brakes been completely cool down, with light pressure braking, the shuddering will show... It doesn't bother me much any more as I swap pads and rotors for the track.

If you hate brake shuddering, do not buy project mu pads. No matter how I tried it, and what rotors I used, it shudders. However it seems to grab well with vitually no brake dust.

 

[nsxtasy]

I'm using the same brake products as you are. I have the StopTech two-piece rotors, and am using the Cobalt GT Sport brake pads. I had tried the Carbotech Panther Plus pads, but like you, I found them to squeal way too much for street use. The GT Sports work fine right out of the box, do great on the track, and rarely make any noise at all on the street. I really like them. The only notable thing I do is, for track use, to make sure to replace the front pads when they get down to 3-4 mm or so of pad material; don't wear them down too close to the backing plates.

No disrespect intended towards those who are using true track-only type brake pads (like the Cobalt Spec VR). Track pads give great grip. But they are just unsuitable for the street, not only due to squeal but also because they need to warm up to be effective. Bottom line, I prefer not having to change my pads before and after each track event, and I am willing to give up a little bite in order to do so (although the GT Sports bite pretty darn well).

To answer your questions...

My question is what do you think caused the pad deposits, was it the rain? Should I always replace rotors and pads together? Do I need to do more stops to bed them, or perhaps less?

I ordered some Cobalt GT-Sport pads (still in the mail) to replace my Panther Plus pads. What should I do to remove the pad deposit and insure that my new brakes are bedded correctly? Should I just try to put the new pad on and bed them in, or should I try scrubbing with a sponge... or should I get my rotors resurfaced... and will this hurt the life of the rotor?

It's not clear what caused the pad deposits and the shudder that you experienced. It sounds like you used the proper procedure. Mostly. You didn't mention it, but you're not supposed to touch the brakes after you do those repeated stops of increasing severity; just drive home without touching the brakes, and let them sit overnight to cool. Also, during the bedding, the brakes should get VERY hot; if you leave your windows open while doing it, you should be able to smell the brake pads, and when you're done, if you look at the edge of the pads (easy on a '91-96), they should look charred, like the first few mm closest to the rotors have turned slightly gray.

You don't need to replace pads and rotors at the same time. But when you change pads - especially switching brands or compounds - you need to go through the bedding procedure again, at a minimum. The other measures you mentioned, like buffing the surface of the rotors with a Scotchbrite pad or turning (cutting) them ever so slightly or throwing on a set of Hawk Blues, to wear off any surface deposits, are the next step, if bedding doesn't take the surface deposits off. But I would just try bedding them properly first, and seeing if that isn't enough to make them work okay without shudder.

 

[VintageracerNYC]

where can I get these Stoptech two-piece rotors and do they fit my 92 with original brakes? This is for a track only car so maybe the PP pads would be best for me huh?

 

[2slow2speed]

where can I get these Stoptech two-piece rotors and do they fit my 92 with original brakes? This is for a track only car so maybe the PP pads would be best for me huh?

www.daliracing.com
www.rp-motorsports.com
www.scienceofspeed.com
www.stoptech.com

Most of the Stoptech authorized dealers should be able to get them, that's assuming that Stoptech has them in stock.

 

[nsxtasy]

do they fit my 92 with original brakes?

The ones made as a drop-in replacement will fit your car.

This is for a track only car so maybe the PP pads would be best for me huh?

Not really. If it's a track-only car, then get some track-only pads, with the highest coefficient of friction and operating temperatures, like the Cobalt Friction Spec VR pads, which are excellent for track-only use. Coefficient of Friction 0.64m, Temperature Range 350-1550F, both of which are higher than the Panther Plus.

 

[VintageracerNYC]

am I reading correctly that these two-piece rotors are almost $400.00 each?

 

[2slow2speed]

am I reading correctly that these two-piece rotors are almost $400.00 each?

The price should be for the pair

http://www.daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=600

 

[s2ktaxi]

I share Ken's philosophy on not having to change pads between street and track. Having used the PPs, they have two disadvantages - They squeel even when driving on the street without braking. The brake dust is harder to clean off the car/wheels (esp. if they've been wet and dried). However, the PPs do have slight better initial bite and slightly better pedal feel than the GT Sports.

I'm using the same brake products as you are. I have the StopTech two-piece rotors, and am using the Cobalt GT Sport brake pads. I had tried the Carbotech Panther Plus pads, but like you, I found them to squeal way too much for street use. The GT Sports work fine right out of the box, do great on the track, and rarely make any noise at all on the street. I really like them. The only notable thing I do is, for track use, to make sure to replace the front pads when they get down to 3-4 mm or so of pad material; don't wear them down too close to the backing plates.

No disrespect intended towards those who are using true track-only type brake pads (like the Cobalt Spec VR). Track pads give great grip. But they are just unsuitable for the street, not only due to squeal but also because they need to warm up to be effective. Bottom line, I prefer not having to change my pads before and after each track event, and I am willing to give up a little bite in order to do so (although the GT Sports bite pretty darn well).