Rotor deposit StopTech Floating/Carbotech Panther Plus

[titaniumdave]

If you are swapping pads for street and track, make sure the pad compounds are compatible. All Carbotech materials are, FYI. I like XP-8 pads for track use.

One thing I learned the hard way is most track pads don't wear on the disk, they are making contact with the pad deposit left on the disk. When you swap pads to street use, the pads are making contact with the pad deposit so one can have un-even deposit of the new pad on the rotor surface, creating pedal judder. If you end up with this, I have had times it is not possible to get the rotors to run smooth ever again. When I am swapping pads back and forth, I will re-bed them every time. First track session, work them very hard to get them up to temperature quickly to transfer a new layer of pad to the rotor.

 

[VintageracerNYC]

while we are talking about Stoptech has anyone installed and used one of their four wheel BBK as of yet on the track? Curious about stopping power and fade resistance for my upcoming 92 GPW racecar!

 

[nsxhk]

So back to shudder issue ......

Should I just go and re-bed my rotors as is or should I go turn my rotors first and then re-bed them properly?

Henry.

 

[Hrant]

Henry a few suggestions - unless you want to cut the chase and turn the rotors. Since the rotors are new, I doubt that within the first session you warped them. Try this first.

Using 150 grit sand paper, slightly scuff the surface of the rotors and then bed the pads per the instructions of Carbotech and or the manufacturer of your rotors.

Also, you may want to get the non-compliance clamp that Comptech or Titaniumdave make to make sure that what you believe is shudder is not the change in the toe/caster from uneven surfaces on hard braking - the sensation would be kick back in the steering. While some assert that street driving becomes harsher especially on bumps, I have not noticed much difference.

 

[2slow2speed]

while we are talking about Stoptech has anyone installed and used one of their four wheel BBK as of yet on the track? Curious about stopping power and fade resistance for my upcoming 92 GPW racecar!

Look for my posts, I installed the 4 wheel Stoptech BBK kit back in 2003 and have done many events with it. Brake feel is excellent, easy to modulate, no problems with ABS, a well balanced kit. Worth the price IMHO.

The only downside used to be the lack of wheels that would clear the caliper without a spacer, there are more wheels on the market now that will clear the caliper.

 

[nsxtasy]

Should I just go and re-bed my rotors as is or should I go turn my rotors first and then re-bed them properly?

Your rotors and pads are already on your car, correct? If so, then try the easy way first. Just go and re-bed your rotors, and see if that cures the shudder (which I'm betting it will). If it doesn't cure the shudder, you can always have them turned later on.

If you are changing rotors or pads anyway, then you could turn them (or try scuffing them with a Scotchbrite pad as I mentioned or sandpaper as Hrant mentioned).

 

[SKB NSX]

Hey Scin,

Wow . . . after your first event at Willow, you have REALLY gotten into this racing ! I was so looking forward to Cal Speedway, but came down with the worst case of the flu and had to stay in bed and miss the event. I'll see you at Buttonwillow next weekend, though.
Do you remember my shudder problem at Willow? I had just changed from Hawks to Carbontechs and had the same problem. Shane at Autowave told me Carbontech just changed the compound and many people have had this same problem. After the race, I took my NSX to a large Park and Ride lot, and made about 10 ABS invoking panic stops and it got rid of the shudder. Try that.
After Buttonwillow, I'm changing back to Hawks.

 

[nsxtasy]

I took my NSX to a large Park and Ride lot, and made about 10 ABS invoking panic stops and it got rid of the shudder. Try that.

That's only part of it. The best way to bed pads is not just to get them hot (as you describe), with a series of stops of increasing severity, but also to then let them cool down without using the brakes at all - either by driving a while on the highway or, better yet, parking the car overnight. This is the recommended procedure by nearly all manufacturers of brake products, including Cobalt Friction, Stoptech, Carbotech, etc.

 

[SKB NSX]

Yes, of course, nsxstasy, I forgot to add that step, assuming . . .

 

[nsxhk]

Thnx for the input, I'll try rebedding them first.

Carbotech changed their compound? Really??

Henry.

 

[SKB NSX]

Well, that's what Shane at Autowave told me about 6 weeks ago and he's always right. They're my first set on Carbotechs, so I wouldn't know the difference. I'm not too fond of the Carbos I have, I'm going back to Hawks after this next race weekend.

 

[Scin]

I'm hooked bad SKB! Taking the car to the track is great.

I'm probably going to skip Button Willow, the car needs a break. I am also worried about a sound I was getting from the left rear wheel last weekend, I am going to take a look at the cv joints and check the bearing this weekend.

I will be at the NSX event Mark is sponsoring on the 15th however, will you be attending that event?

I don't think you missed much by skipping California speedway (sorry to hear you got sick). That track has a lot of walls to hit and it was nerve racking in the rain. A lot of people did serious damage to their cars that weekend.

Hey Scin,

Wow . . . after your first event at Willow, you have REALLY gotten into this racing ! I was so looking forward to Cal Speedway, but came down with the worst case of the flu and had to stay in bed and miss the event. I'll see you at Buttonwillow next weekend, though.
Do you remember my shudder problem at Willow? I had just changed from Hawks to Carbontechs and had the same problem. Shane at Autowave told me Carbontech just changed the compound and many people have had this same problem. After the race, I took my NSX to a large Park and Ride lot, and made about 10 ABS invoking panic stops and it got rid of the shudder. Try that.
After Buttonwillow, I'm changing back to Hawks.

 

[SKB NSX]

It's so easy to get hooked . . . but I'm glad another NSX'er has joined the NASA SoCal group. We can learn from each other.
I still wish I hadn't gotten sick and could have attended Cal Speedway, I've never driven it before and it's only on the schedule once a year.
Too bad you can't make Buttonwillow, it's my favorite track, fast, technical and challenging. I'm still having an entry and exit oversteer problem that's frustrating, but I'll get it solved eventually.
Hope to see you at the event in May !

 

[Hrant]

Shane at Autowave told me Carbontech just changed the compound and many people have had this same problem.

I beg to disagree. I talked to Larry Narcus the owner. It's best to get such info direct from Carbotech and they do have a toll free number.

Some 6+ years ago, Carbotech changed from carbon metallic to ceramic pads, but the compounds have not changed. What has changed is their product line. XP9 is being dropped because the XP8 or XP10 fit the bill, and XP11 will be dropped because a better pad, the XP12 is being introduced.

If I followed Larry's techspeak, pads that we are discussing come in carbon metallic or ceramic materials. Carbon metallic pads at high temps form ion carbide. Ione carbide has the advantage of reducing the wear rate of the pads because it is harder, but the disadvantage is it has a tendency to create grooves in the rotors because it is harder. It has some corrosive materials, and lacks the modulation offered by ceramic pads, and needs higher temps to work. For true racers, the carbon metallic pads may be perfect - it is not for everyone.

Finally, how a pad is embedded and cooled down has much to do with shudder. And after 6 years of tracking and instructing for some 5 years, I can tell you that most of the brake issues stem from 4 variables: (a) over braking; (b) poor embedding and cool down of the rotors; and (c) poor choice of pads for the type of driving; and (d) poor brake caliper match with the driving-track/car weight/pad-rotor combo - unlike other cars, the NSX's OEM calipers are not a poor design. For those who track their cars (but not dedicated racing) and have issues with the P+, try the XP8 per Larry's recommendation.

Carbotech's focus is more on lapping days drivers - and based on their sponsorship of sanctioned events, they rarely hear of such issues from their clients. We just had a local group buy of 12 Carbotech sets. YMMV.

Edit: ie-spell check failure!

 

[VintageracerNYC]

thanks for the info HRANT..

 

[SKB NSX]

Thanks for the correction, Hrant. I didn't call Carbotech, as you did, it was just a casual conversation with Shane.
I've raced many cars in the past, and do know how to bed pads, and my Carbotech's are fine now. I don't drive my NSX on the street much, generally to the track and back. I'll call Shane and give him the info from Carbotech.

 

[nsxtasy]

It's best to get such info direct from Caltech and they do have a toll free number.

Some 6+ years ago, Caltech changed from carbon metallic to ceramic pads
.
.
.
We just had a local group buy of 12 Caltech sets. YMMV.

 

[OLDE GUY]

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

I had the same problem when I went with new rotors and new pads at the same time on a Porsche 944 Turbo. My race shop "bead blasted" the deposites off the rotors and I re-embedded the same pads which corrected the problem.

 

[Scin]

I installed my Cobalt pads and powerslot rear rotors over the weekend. I also sanded my front rotors with a 150grit sanding sponge. I then re-bedded my rotors and it looks like my shudder problem is fixed! I will have to see how the brakes do at the Pahrump this weekend.

My first impressions of the Cobalt pads are favorable. They don't squeek like the Panther Plus and they have a nice feel to them. They have noticeable less bite then the Panther Plus, but better then stock.

 

[titaniumdave]

Sounds like a nice street pad. Let us know how you like them on the track.

 

[Scin]

I just got back from the Dali event at Parhump. It was fun, the weather was nice... and it was the most NSX's I've seen in one place. Hi to anyone I met there.

The good news is my brake shudder is gone. The bad is that I don't like the Cobalt GT's on the track nearly as much as the Panther Plus. The brakes were adequate, however I got them into the upper end of the temperature range several times. When they were this hot they were much less effective.

The Panther Plus were always fantastic and I never had any fade what so ever, they only seemed to get better when hot. I can see how the Cobalts are great auto cross and high performance street pads. The Panther Plus are great on the track and street except the squeeking. Now I understand why all my instructors were so impressed with the brakes on my car, a lot of it was good pads.

I'm tempted to try the Dali street/track pads, does anyone have experience with these... how do they compare to the Panther Plus or Cobalts?

 

[nsxtasy]

The bad is that I don't like the Cobalt GT's on the track nearly as much as the Panther Plus. The brakes were adequate, however I got them into the upper end of the temperature range several times. When they were this hot they were much less effective.

That's totally different from my experience. I've gone through several sets of Cobalt GT Sport pads on the track, and they have always been absolutely outstanding, with absolutely no fading or ill effects from heat. They have performed every bit as well as the Panther Plus - even better, when you consider that they don't squeal on the street. I just drove over 350 track miles on them this past weekend at Putnam Park, took 2/32" of tread off my R compound tires, and the pads held up beautifully. In fact, everyone I took for a ride commented on how great the brakes on the car were.

If you're going to use pads that squeal all the time, you may as well get track-only pads (like the Cobalt Spec VR)...

 

[NSXDreamer2]

That's totally different from my experience. I've gone through several sets of Cobalt GT Sport pads on the track, and they have always been absolutely outstanding, with absolutely no fading or ill effects from heat. They have performed every bit as well as the Panther Plus - even better, when you consider that they don't squeal on the street. I just drove over 350 track miles on them this past weekend at Putnam Park, took 2/32" of tread off my R compound tires, and the pads held up beautifully. In fact, everyone I took for a ride commented on how great the brakes on the car were.

If you're going to use pads that squeal all the time, you may as well get track-only pads (like the Cobalt Spec VR)...

Ken, but the track layout is different and you have massive air feed in opposed to Scin's setup. IMO. I also never had any brake fade with PP, I also got rid of the shuddering after I rebuilt my calipers and sanding the rotors. But then I'm in the NW. and the tracks here had long straightaway cooling brakes down.