Looking for feedback on Zo7 pkg carbon brakes and cup tires.

Plan on using GS w Zo7 pkg:
- Mixed commuting/high performance street 90% of the time.
- Track road course 10% of the time.

I don't spin the wheels excessively and try to balance momentum, braking and speed when at track.

To those with Zo7 upgrade, how many estimated miles can I expect out of the tires, pads and rotors?

Thanks for the feedback.

 

That is hard to answer since it is based so much on experience level.

The CCM brakes are very good, however, their life time is not as great as it needs to be for the replacement cost. I got 13 track days out of a set of rotors with 11 days at VIR and 2 at Watkins Glen. I went through 2 sets of front pads and one set of rear pads. I may have hastened the demise of my front rotors by using a set of Carbotech XP10 pads which seemed to expedite the wear of the rotors (I noticed the surface of the rotor changing/pitting after the first event running them). I am of the opinion that despite the claims made by various pad manufacturers if the pads aren't designed to work with Ceramic rotors it is probably best not to run them.

Looking at spending another $3100 to replace the front rotors and the almost brand new pads that were ruined by some deep grooves on the rotors I bit the bullet and replaced the fronts with the Essex AP Radi Cal kit.

My first time on track with the car and the Cup2 tires was in the rain. With the car set in the Track mode and in the Wet sub mode it behaved quite well on the Cup 2s. After a couple of wet sessions the track dried and I ran a dry session with them. They performed very well. After that I changed over to my track wheels with 315 front and 345 rear Hoosiers. The next time I ran the Cup2s on the track was after I corded the Hoosiers. I ran the Cup2s for 6 sessions and they performed very well but afterwards I noticed an unusual wear pattern on the left rear tire. The track I was running on had a right hand turn that was sharp and curving steeply uphill in a short distance. As the car crested the top of the hill the left rear tire would break loose just a bit (even under light throttle) and a section of the tread about 2 inches inward from the inside edge of the tire just sort of peeled off the tire. The dealer replaced both rear tires although the right side tire was worn evenly and had as many miles left on it as the front tires had. That was in June and I have been using the Cup2s on the street and have added a couple thousand miles to the fronts and they still look good although worn on the outside edge.

There are several people on the forum who have been purchasing Cup2 take offs and using them for their track tires and setting some pretty fast lap times with them. Based on what I have seen and experienced the Cup2s are competitive with the Hoosier R compound tires, have the advantage of being run flats but if purchased new cost about $800 per set more than a new set of Hoosiers.

To give you an idea of where my driving level is I have a total of 17 track days on my car this year. 13 at VIR, 2 at Watkins Glen and 2 at Carolina Motorsports Park. I am an instructor and am working on trying to reduce my lap time at VIR from 2:07.9 which is my personal best. There are forum members who have turned 1:59s at VIR with the Cup2s. I met one guy who had just purchased his Z and once had it set up in the proper track sub mode turned a 2:03 in his first session on new Cup2s.

The main issue with both the tires and the ceramic brakes is consumable cost Vs performance.

Bill

 

Edit: After posting up, I noticed the Tech Contributor Bill Dearborn had posted up very good info, and I'll defer to his thoughts!! Bill has a lot of track time, and much more than I do in the C7 Z06. I have a C6 ZR1 with the same brakes, and I've always used the stock pads on it. With about 15 to 20 track days on it the rotors are starting to show some pitting, and I've got the 3rd set of pads on it now. It's a street car now, so I'll keep an eye on the pads to see what the pitting on the rotors does to the pads for street driving. Like Bill says - these carbon ceramic brakes are kind of expensive consumables. I've got a set of brand new front and rear rotors and pads sitting in my garage - I jumped on them when I saw them for sale and was able to get the whole package for $3500!! With a discount from a forum vendor, front rotors and pads alone would cost almost $4000!!
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First of all - if 90% will be street driving, I'd strongly suggest getting another set of wheels with Pilot Super Sport tires for the street. The Sport Cup 2's aren't good in the rain, and neither the Cups nor PSS are very good when temps get down below 45° or so.

I got another set of OE wheels with PSS for street driving my Z07, and save the Sport Cups for the track (I trailer the car, so I don't have to drive 650 or 700 miles on my Sport Cups to events at Bowling Green or VIR).

Actually, the Ron Fellows Corvette Driving School at Spring Mountain takes off the Sport Cups and puts PSS tires on all their school cars, and the PSS is not much below the Cups in performance.

As far as street miles - I think I've read that owners are getting more than 10,000 miles of street driving on the Sport Cups, and up toward 30,000 on the PSS.

On the track - I dunno! But, based on my experience at 2 track events so far with the car (one 2 day, one 3 day), the Sport Cups still look great after 5 days of track driving with four 25-30 minute sessions/day. The tires still look great and I hope to get at least 10-12 track days - maybe more. As far as track mileage, I'm figuring 3.5 mile tracks like VIR or Daytona, during a session I get 10-12 laps for maybe 40 miles, four sessions/day, so let's call it 150 miles/day.

So....if I can get 10-12 track days, I'll get roughly 1500-2000 track miles out of them, unless they start to get greasy or heat cycled out.

Bottom line:

• I recommend a set of PSS for the street - save your Sport Cups for the track
  
  
• Keep your eye on the C7 "For Sale" section, or check the forum wheel/tire vendors (like Bob at HouseOfWheels) - I got a set of OE Z)^ black wheels with low miles PSS tires and sensors from another forum member for IIRC something like $2500.
  
  
• As far as pads/rotors - I dunno that either! But, I'm thinking maybe 6-8 track days for the pads, and I just don't have any idea about the rotors yet.

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Just saw replies after.... Thanks!

 

I was told by one of the service people at Ron Fellows that with normal street driving, it is unlikely you will ever need to replace the carbon rotors, just the normal pad replacements really. They last WAY longer than steel rotors do. The only thing about them is... they are very brittle, and therefore very fragile and prone to chipping. If you just bump them with a rim when removing the wheels, it will chip them and require replacement (at like $1600 a piece), so you need to be really careful when removing/installing wheels.

 

I don't know, I get only 5 days out of the PSS tires, so I have to believe that the Cup tires are going to be half that if I'm lucky. Which is why I haven't bothered to use the Cup tires even though they are now available in Z51 sizes.

 

Cup tires are not very good, anyway. They do overheat fairly quickly, just like PSS, and then you'll destroy them very fast with the gooey material wearing away.

I would highly recommend tires much more resistant to heat and consistent throughout their life, like NT01, Trofeo R, etc.

 

That is true. They do last much longer on the street. However, the iron rotors will last a long time on the street as well. Given the low miles on most non-track Corvettes they could easily last through 2 or 3 owners and not need replacing until the cars are 10 to 15 years old. Most owners of C5s and C6s replaced their rotors and pads because they were overly concerned with non existent rotor warping, brake pad squealing or brake pad dusting. All you have to do is scan the forums and look at what they are complaining about and wear isn't one of the hot buttons.

Bill

 

Unfortunately that means changing wheel sizes. Been trying to avoid that.

 

My 2 cents.

I have driven 7500 miles on the cup tires (no track time) and i'm just now replacing them.

I have driven the car in the rain with cup tires and did not crash, I simply put the car in weather mode and took it easy and had zero problems, both on the highway and curvy mountain roads.

 

I think you're looking at this the wrong way. The Cup 2 being a DOT 'R' spec tyre is going to handle heat and the other stresses on track better than the PSS, even though the PSS is an excellent track tyre for an ultra high performance street tyre. Hence lap for lap; session for session , and HPDE weekend for weekend, I believe that there will be less wear on the Cup 2's than the PSS.

Hence you'll be faster and have tyres that last longer on track with the Cup 2's.

Bish

 

I would be nice if this was the case. Has anyone else seen this behavior?

I've only got one more track day this year, but if this is the case, perhaps I'll give it a shot next season.

 

What do you mean with behavior, the overheating issue? If so, yes, PSS tires overheat in a hurry, in about 2-3 laps, and never come back until properly cooled down in my experience. This behavior actually makes them great for wet travk use.

Cup 2 tires resist heat more, but they're also surprisingly bad in terms of heat resistance for an R compound tire. Trofeo R, NT01, R7, R1, Z214, A048, etc. all have much better heat resistance.

 

The only problem is if you want to run stock wheels the Cup2 and either the A7 or R7 are the only tires that fit. From my standpoint the Cup 2 is competitive performance wise with the Hoosiers although being more expensive.

Bill

 

Advantage Bill is that you drive the Cup 2's to/from the track.

 

I don't see R7 in Z51 sizes.

I do see the Trofeo R in a close enough size to use, but I haven't see a head-to-head comparison between those and the Cup2.

 

If that's what you meant, I don't think anybody uses stock sizes, including GM; IIRC, they used 265 fronts 305 rears(?) on their SEMA car slated for Michelin cup, made by GM Performance parts.

 

I don't see the R7 available in a 20" at all, perhaps they drop the wheel size.