I just got back from the new Reno-Fernly track with the st43's in the front and the rear. These pads have so much bite it took me 3 sessions to get used to them! Here's how my day progressed with these pads.

1st session. I did a warm up lap to get heat into the tires and brakes. The new Reno track is very fast and has a set of esses at the end of the front straight that can be taken at @100, but you quickly have to get on the brakes and slow to about 40 before entering the long decreasing radius left hander. So I applied the brakes and they bit so hard, I almost lost control of the car! Holy cow these things grab! I also had a little shimmy develop in them as well telling me that weren't properly bedded. I was really regretting my pad decision at this point.

Since the track is in boonies-ville, I decided to bed them in a little on the deserted access road. I did a few 60 to 0 stops. After a few of these, I got a better sense of how they react at the threshold braking levels. The shudder went away after a 3 or so of these stops and I had a better feel for how they react to pedal input.

Bedding the brakes helped me out quite a bit in terms of knowing how the brakes would react to hard stopping and the next session I was a little more confident in them. I was still greatly struggling with my hub flex. Every turn I went into the brake pedal lowered to a different position before grabbing making heel-toe downshifting smoothly a challenge. My rhythm was totally thrown off. It wasn't until my third session where I was able to fully utilize the pads by pumping the brakes before every braking event to get the pedal back up to the top. Is anyone else struggling with hub flex??

The overview of these pads is that they have so much bite, I can't see anyone but a truly experienced track hound using them to their fullest. I never would have imagined that changing brake pads would require a full day to get used to, but it really did. The jury is still out if I will buy these again or just go with pf-97’s next time. One thing is for sure is that they will last me a long time. The rears have hardly taken a hit after two days so I expect to get a good 8 days out of them. I’ve got many track days lined up in June so I’ll post back if I’m ever able to get used to these beasts. If I didn't have the awful hub flex, I think I would be very happy with these pads, but since they're so sensitive I'm not sure they're the greatest choice for Z owners.

 

heh - the hub flex / pad knockback issue is pretty brutal - read more here:

http://www.stoptech.com/whitepapers/knockback.htm

i wish there was an answer to fixing it, but i've yet to see one. i've resorted to the same thing - i'm usually left-foot dabbing the brakes as i approach a braking zone. i think part of the problem is that the calipers are almost at 12 o'clock, whereas if they were at 9 or 3 o'clock, the angle of deflection wouldn't be so bad. regardless, without relocating the calipers or replacing the suspension components with beefier pieces that don't flex as much, i don't envision a fix. jritt assured me and others that it isn't a safety thing (as in, the suspension parts won't break from it), i have my doubts. i believe over time, these pieces will eventually fatigue enough to fail. scary as hell. since i'm not a metallurgist or have enough background in that discipline, i can't speak to whether the aluminum's flex is more or less likely to cause a fatigue failure (than say, a steel substitute). of course, the complex shapes of the parts means that stronger replacements are probably not likely to come out anytime soon, and if they do, they'll cost a small fortune.

as pertains to the pads, i *STILL* haven't had a trackday on the axxis ultimate rears - had a bunch of job stuff going on which meant no committing of funds to fun stuff for a while. now that that is resolved, time to go play again! i'm hoping that for the $40 they cost, perhaps in conjunction with the Ti backing plates (when/if they become available) that will put my rear pad performance back in the game. having more CoF at the back isn't really what i'm looking for - similar grip to the hawk hps would be fine, so long as they hold up to the heat.

i've written off the dust boots. bottom line - the car, driven hard on the track, is going to demolish them. caliper temps just get too high for any of them to survive. so - whenever i swap pads, i just take a can of brake cleaner to the calipers and wipe the exposed piston area down. so long as there aren't any burrs or nicks, it isn't a problem. if you let them get real grungy, then push them back in to put in new pads, you will nick a seal, which will be a problem. keep 'em clean, and it won't make a bit of difference. my biggest concern will be during the winter - you don't want salt collecting on the pistons because it will corrode them. wash them down with a hose if you're driving in the salty slush, and they should hold up fine.

ahm

 

hey dave,

as i was leaving the track yesterday i noticed my right front rotor squealing pretty bad. changed the pads tonight and got the whole story. the inside front pads were both bare metal; left front slightly worse than right. i'm sure that's where my brake fluid was going.

additionally, i melted both rubber piston boots in the front and was a little worried until i read this thread.

bottom line, like you were telling me, NISMO pads won't cut it at the track. thanks for the tips and hope you don't mind if i keep picking your brain.

kyle

 

Just found another benefit to these pads.
The dust is not corrosive. I just swapped tires and washed the car. The brake dust (which was on very thick) washed right off. No scrubbing! I've seen pf-97's ruin wheels and paint on the side of the car.
Also upon looking closely at the pads with the wheels off they showed little to no wear. Even the rear looked brand new after 2 days. The rotors looked good too. If only I can learn to modulate these, they will be a good value despite the high cost. I'm practicing my left foot brake pump up action on the street to tame the severe knockback so the next track day I'll be more prepared.

 

are your dust shields still intact? with the shield in place, it seems the inside pad sees significantly higher temps, and it will demolish the respective pad. i cut mine off even before i went to the 13" stoptech kit, but it wasn't even close to enough of a difference to matter. as has been noted many a time here, if you don't have the track brembo's, the oem brakes simply aren't big enough to survive track use.

ahm

 

One more update for everyone..
I had one more track day at buttonwillow, which is not too terribly hard on brakes. At the end of the day when I swapped back to street pads and was able to get a good look at them, I was amazed at great they are wearing. The rears have only worn about 1-2mm after 3 days. I'm upping my estimate that the rears will last me at least 10 days. My rotors are perfectly smooth too, although the rears are getting slightly cracked.

I still think they have too much torque and probably won't buy them again. I am not able to trail brake without upsetting the chasis. Dropping the anchor in a straigt line is amazing provided you can stay out of ABS land.

I think I have discovered that if you choose the right rear pad, you can live with the stock rear setup. I really believe that people running those high performance street pads on the track are going about things all wrong (even if they are cheap). I can change all 4 pads in under 30 minutes have confidence that I will run all day fade free.

 

Dave,

If you're soliciting suggestions for another pad, I have the 13" Stoptechs and use the N-Tech house brand "lapping pads" with very good results.

The pads have enough cold bite to install the day before and drive to the track on. They're easy to modulate, have very natural feel at medium high speeds and good fade resistance. I have 5 days on them and they've shown excellent wear charecteristics - not even 15% worn yet. 3 of those 5 days were at NHIS, a track that's pretty hard on brakes.

The only issue could be layering your street pad material on the track pad stuff. When I re-bed the street pads I can't seem to get enough heat into the rotors to burn off any uneven track pad deposits. The street pad material (Axxix Ultimate) builds up on the track pad stuff so they get a little lumpy for a while, a little pedal vibration, not too bad. The pad material gets scrubbed smooth again - so far - on my next track visit. Overall I'm very satisfied with the pads and you may want to consider them next time around.

 

Run your track pads for a day after the event. Running below their operational temperature, they will be very abrasive and will cut troughs their own pad deposit. (“un-bedding” themselves.).

I do this and it helps a lot.

 

Thanks Kolia,

I'll try that next time.

 

One more update. I bought a set of dedicated track rotors because I was having such a hard time bedding these bad boys in.

The insane bite and difficulty modulating the brakes was gone! They bit like normal (track) brakes. The secret seems to have been dedicated track rotors. Perhaps the pad material was not compatible with the street pads.

I don't have any reservations recommending these to those who are willing to buy a second set of rotors. I think the extra 10 minutes spent swapping the rotors saves you 30 minutes of abusing your car to bed the pads.

I've done about 6 days on them now and and have more than 1/2 left. The front (stoptechs) and rear (oem non-brembo) seem to be wearing at the same rate.

 

I have gone to Waterford Hills (Detroit Area) for 4 track days so far. It is a small 1.4 miles track with lots of turns. It's a fairly technical track and is not too hard on the brakes or tires. I have the non Brembo setup and have used the stock OE pads the first couple of days. These worked out OK for me as I was gaining experience. I did wear out the rear quickly and switched to rear Hawk HPStreet as the HP+ is not available for the rears. I eventually changed the front to the HP+ for my 4th day and planned to use these only on the track and keep the OE or a set of HPStreet for street driving. I noticed that when removing the OE pads, they were worn at an angle (I created on thread on this a week or so ago) but did not notice any banana shape of the pad/backing plate. The HP+ worked great but wore approx 1-1.5mm in pad thickness in one day with about 90 track miles. My rotors, after the 4 days at Waterford Hills were like new in the rear (16mm) and for the front were down to 23.5mm (24mm new).

Next event was this weekend, 2 days at Gingerman (western Michigan) with RSR PCA. This is a 1.9mile track that is known to be hard on the brakes and tires. The surface is very abrasive. I had previously purchased front and rear Hawk Blues but later read your warnings of staying away from them due to high rotor wear. I was not planning to use these but brought them anyway.

Fronts: I started the Saturday by removing my street pads and putting back the slightly used HP+. I noticed that the dust boots were slightly damaged from the heat. I was not too worried, but did not like it. I was able to run all weekend with these (210 miles). I noticed on Sunday that there was some deposits on the rotors but did not feel anything in the pedal. At the end of the weekend, I removed the pads to place some OE pads on for the 200 mile drive back home. The HP+ still had material on them but were worn at a severe angle and the backing plate was bent like a banana. I need to look at them closer tonight and will update with more details. The pad material was missing in some spots and had left quite a bit of material on the rotor. At that point I thought of putting on the Blues and drive a bit to clean it up but I was not about to do 2 pad changes in a row on a Sunday night. I will do this tonight or tomorrow as the pedal shakes from the uneven deposits. It is less severe than at first but the OE pads are not abrasive enough to clean it up properly. As far as the boots, they are pretty much destroyed. I wonder if the boots melts, won't the seal melt also? Some of the rubber bleeder screw caps also melted. Should I remove the piston to get all the pieces of rubber out from the cylinder body or letting some rubber in there be OK? Bottom line, the HP+ may have been OK for Waterford but definitely not for Gingerman.

Rear: For the rear, I kept the HPstreets on (they had 2.5 track days and some street miles). Coming in the pits after the 4th session on Sat, I heard grinding and though they were worn to the metal. I also had a 4 ft steak of brake dust from both rear wheels right behind the car from when I parked... It turns out that the grinding was the wear indicators, so no damage was done. All I had in my tool box was a new set of OE pads and the set of "don't put on your car" Hawk blue. Since I needed the OE's for the drive home, I decided to go with the blues. I used them for the last session of the day and then removed them for the 30 mins drive to my hotel. I put them back on the next morning at the track. By now I'm tired of swapping pads while the PCA guys are asking "what's wrong now". Most of these guys drive to, on the track, and leave with the same pads. Not one change! Of course the ones that trailer the car, may have more aggressive pads that they would not want to drive on the street. Bottom line is that they have brakes that can take the heat and not wear out. One of the guys has a semi race prepped 911 and has maybe 20 days on his pads. Anyway at the end of the day the Hawk blue pads looked good, had some wear (I'll measure them tonight) but no crumbling. The rotor was still at 16mm, so no wear of the rotor. Is this a pad that you guy's have tried in the rear?? Maybe the comment of high rotor wear was mostly for the front rotors. I like the blue in the rear and will be using it again. I'll collect more data and post later this week but these seem to have worked for me and on a hard braking track. I’m still considering what I should do about the boots. They can be purchased at PerformanceNissanParts.com for around $22 for either Frt or rear pairs. Installing new one would be a waste, as they will just melt again next track day…

Your comments are always appreciated.
Martin

 

The comment on the high rotor wear is only when they're cold. Drive them around on the street for a week and you'll see what I mean.. They're a viable track pad and still used by many. I just think there are better pads for the Z.
If you've got them, by all means use them in the front and rear, they're worlds better than the street pads you mentioned. You probably could have gotten away with using them for your 30 minute drive to your hotel.

I hope you showed those porsche guys a thing or two out there

 

I was just up at Gingerman last weekend with Chicago PCA. I don't have a problem with brakes, but with tires holding up at that track.

Anyway, I would recommend that you remove your front dust shields as well if you haven't already. I am quite content with Cobalt Friction Spec VR pads, and while I don't drive them around in the street, I do put them on before driving up to an event and take them off after driving back (2 hours to Gingerman). It sucks changing pads at an event, plus the rotors get extra clean during the drive. Others seem to like the Carbotech XP10s, but I am not a huge Carbotech fan anymore. Plus Matt will probably not allow you to buy anything better than the XP8's with the stock brakes.

As for your dust boot, I had the same problem back when I had the stockers. After changing them, it looked worse than it really was so I would say just leave them. I would spray them with brake cleaner before pushing the pistons back in though.

I would say that you are at a crossroad where you could either upgrade to a BBK or try to get by. I have a 13" kit (all four wheels) and that was more than adequate for me. Although if I did it again, I would get a 14" kit up front since I never use 17" wheels. You could defintely get by with just a front upgrade though, the rear pads just don't last long.

 

+1 for the Spec VRs.

Just got back from Le Circuit Mont Tremblant (Quebec, Canada) and they worked very well. I also drive to and from events with the track pads. I'll never run a track event on street pads. It's not worth it and spoils the fun when you run out of brakes after 5 minutes of lapping...

My brake fluid had a hard time tought. I had to bleed them every days. I use the Willwood 600 fluid.

 

Thanks for the responses, plenty more questions for you.

Dave, after how well the rear Blue performed, I’ll definitely try them on the front. Next track day is going to be mid September. I am almost certain that someone was saying that they eat the rotors on the track. Whoever it was, he was saying the even if he changed them in the pits, they would still damage the rotors. I’ll soon find out.

StaticCling, it was my first time at Gingerman. Yes it’s very hard on the tires. The left front is in bad shape, probably should have rotated them left to right for Sunday. With no rain, the direction does not really matter. I think my fastest lap was probably around 1’48.5. First time there and not pushing my luck as I need to drive home at the end of the day. I think a group of Z’s from Chicago were there with you right? What kind of lap times are the experienced guys doing? There was a guy from Chicago that showed up for Sunday only. It was not a good day for him. He apparently has 10 yrs experience with miatas and showed up with tires that were pretty chewed up with previous track days. Tires were fine though, just telling me that he drove like mad. I was hoping to get some insight on his brake pad experience but it turns out that he still had the original pads on ! He said he learned from the underpowered miatas to carry speed through the corner and was not hard on the brakes. Needless to say, he wore out the rear on the first session and was done for the day as he did not have spare pads. He did run pretty fast at 1’46” or so but was all over the track and got all 4 wheels off on the first lap after his warmup as well as some other spins at turn 1.

Where is a good place to buy the Cobalt Friction VR Specs pads? Do you know if they make them in both front and rear OE configuration. It’s something I will look into giving a try. Same questions on the Carbotech for web site and availability. As for the front dust shields, they are still on, I did not have time to remove them yet. For the dust boots, you are recommending to just remove them and clean up to hard rubber residue of the piston and not bother replacing the boot right?

Which BBK did you get? I don’t really like the options so far: $4k for a 4 wheel upgrade, ouch.


I should look into going to an event with the Chicago group. There’s a Grattan MSR PCA weekend event in a month or two but that’s full already. I may just go take a look for the day.

Kolia, Mont Tremblant is supposed to be great. I have never been to the track but my cousin is VP of Rennsport PCA, that’s their home track. I’m originally from Quebec. Looks like you have a Track with the Brembo’s. I’m starting to regret not going that route. Did your dust boots melt also?

I don’t know what the boiling point is for Willwood fluid but I heard that Cartell has a Dry boiling point of 570F which is higher than most like ATE (I use ATE blue). Drawback is that it’s not too good wet but if you change it right before the event, it does not matter.

 

The Spec VR can be had directly on Cobalt Frictions web site http://www.cobaltfriction.com/ and yes, the Spec VR are availlable for all Zs.

Tremblant is a great track. Challenging and rewarding, the forested scenery reminded me of the Nurburgring. It's a lot of fun !

My dust boots are still okay. The paint is having a hard time ! Gold calipers are now more bronze and the red Brembo text is almost brown... hihihi

 

I assumed there were better sites to buy from. They also sell Hawk and the prices they show are pretty high. I have used www.raceshopper.com before and they had good prices. They don't carry Cobalt.

 

They sponsor the race team here so I get a nice discount. I didn<t see the need to shop farther...

 

Yeah, I buy the cobalt friction from the website directly. Alternatively, the Carbotech site is located here. Just make sure that you get at least the XP10 compound, I had problems with the XP8 and XP9 (deposits). I never tried the 10.

I wouldn't necessarily remove the dust boots, just leave them be is all. Don't go to the trouble of changing them, unless you really feel it is necessary.

I went with the 13" front Stoptech kit and then got the rear 13" this year. The kit works and it was an easy install. Three other guys are running the Stoptechs. The AP racing brakes are another option, one of the guys is running them. I have no experience with Willwood. The stock brembos might be acceptable, one of the guys had them and did not like them, but with different rotors they might work. The rear brembo definitely is more than adequate, it is just the fronts that might be too small.

I have not done much to the car besides BBK and Wheels (with street tires), but I got a 1:41.9. It is tough sometimes in traffic and running with Porsches because they seem to wait three laps trying to shake you the whole time before letting you pass. Another guy with R compound tires and a host of other mods including the 3.9 FD got a 1:36.

Yes, come out to an event with us. A couple of people got into the Grattan event, I did not though. The next big event we are doing is this Thursday and Friday at Blackhawk farms (South Beloit, WI) and then up at Road America with CAROC in October. I might go down putnam park in September as well with another PCA group.

 

+1 on the I think I'm fast cuz I drive a Porsche stereotype !