When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The 1:33 was in my Z06... on the tires pictured above... late last year. With my ZR1 three weeks ago, on those same tires, I did a 1:30 (with traffic). I didn’t mention it because no other ZR1’s have run Mosport yet (as far as I know) so I don’t have a comparative. I’ve been trying to get Ron to post a lap time, but he never got a chance during the IMSA weekend when GM had the ZR1 pace car here. I offered to let him use mine but he is waiting for his own car to arrive. Regardless, sub 1:30 is very respectable at Mosport... certainly NOT considered “slow”.
Sorry to derail your thread, if you have any videos of your laps, I'd like to see them. I have no doubts you can hustle your car around.
I’m not even sure how relevant comparing tire life across different tracks is. Surface temp, driving style, avg pace, duration of session, alignment are some of the variables needed to taken into account on top the track itself.
heres a non car example. When I raced bikes at the local tracks (sears/thunderhill/buttonwillow) each track was significantly different on how it treated the tire. If you ran the same setup at sears and thunderhill, you could blister your rear tire at thunderhill in maybe a session. We are taking same rider, exact setup and so forth. Then you goto buttonwillow and now it’s the front tire that is suffering rather than the rear.
i use bikes as an example because they tend to show this disparity between tracks in relation to tire wear almost immediately.
Comparing tire wear as in this thread has very limited purpose unless you’re talking about some abnormal tire wear that could be related to a bad set, severe alignment issues or out of range pressures and temps.
I think you were being modest, you handle that car pretty well. Considering you couldn't have had it all that long, more seat time will help too. Was that your first weekend in the car?
I think you were being modest, you handle that car pretty well. Considering you couldn't have had it all that long, more seat time will help too. Was that your first weekend in the car?
Thanks for the compliment.
We don't get "weekends" here... they are single track days, usually a weekday, 9 - 5pm with track closed for lunch hour. These videos were from the July 11th 6th Gear Track Day... it was the 2nd time I had the car on the track and first time I really had a chance to open it up. Having said that, I find the ZR1 to be a very smooth transition from the Z06 I ran all of last season. Obviously more power and better aero, but "feel" and handling are so similar to the Z06 that transition was very easy.
Biggest issue I had with the Z06 was the constant "managing" of the heat issues. Having to paddle shift and short shift just to stop the car from cutting power and limp mode... constantly dealing with the various "bugs" that GM had to fix last year (cooler pump cavitation, trans programming issues, P0106 codes, etc.). It took away from the track experiences and caused this constant apprehension every time I went out. So... getting into the ZR1 has been a dream. All of the heat issues are gone. I don't HAVE to paddle shift, I can literally let the computer do all of that and focus on the driving and track. I'm not constantly waiting for a "code" to be thrown and "limp mode" to kick in... I just drive.
And the car is better in so many little ways. It's more stable feeling (especially at high speed)… and the power is insane. I have no doubt this car is capable of a 1:22 - 1:23 in the right hands. I'm not that guy, but I think 1:27 to 1:28's might be achievable for me. Regardless, I'm having a blast and (the point of my post) I have found I don't need to burn through tires and brakes to do so.
See that's where you're wrong, Im not judging your speed by how many heat cycles you got, I'm judging it by your claimed lap times. I've done laps back to back with pros, in same cars as pros etc. There are no large deficits, if any. I've been in similar/same car as Randy at a couple tracks too. Besides, as far as I know you still don't drive on any tracks as tire friendly as Road Atlanta or Mosport. Remember, I said it's not just about the driver.
Now that's out of the way, 30 heat cycles in a full bodied car on a slick tire? Let's see some videos and some laps. We can judge the speed from those. Since we are being all judgmental up in here. Then maybe I can tell you if your tire wear is sufficient for the compound of the tire. Or if you are pushing your tires hard enough. Maybe it's you who needs to downgrade. See what I did there?
What about the claimed times? They're even posted on Corvette Forum and Randy's is public as well. Running sessions at Thunderhill 2 mile in the 1:24 to 1:25 range eats up an entire set of Cup 2 in just 3 track days (5 sessions @ 20 mins). If you are as fast as Patrick, ie. 1:18 range, then that gets cut down to 6 sessions per his post. If you read the details he doesn't even go ham 100%, in order to save the tires he runs cool down laps. What is ridiculous is that by your token there is a driver out there that can run at Patrick's pace and only use up a set every 6 track days and 3,500 miles on the road. That's just patently false.
I run Formula Atlantic tires on a car that's heavier, underpowered, and has no aero compared to the FA car. So while the compound is R25B (hella soft by any measure) I can still run the entire season on them. I have confirmation from Hoosier that they're softer than the A7 compound. Did you say A6? That's a discontinued tire isn't it? When is the last time you drove on A6?
What about the claimed times? They're even posted on Corvette Forum and Randy's is public as well. Running sessions at Thunderhill 2 mile in the 1:24 to 1:25 range eats up an entire set of Cup 2 in just 3 track days (5 sessions @ 20 mins). If you are as fast as Patrick, ie. 1:18 range, then that gets cut down to 6 sessions per his post. If you read the details he doesn't even go ham 100%, in order to save the tires he runs cool down laps. What is ridiculous is that by your token there is a driver out there that can run at Patrick's pace and only use up a set every 6 track days and 3,500 miles on the road. That's just patently false.
I run Formula Atlantic tires on a car that's heavier, underpowered, and has no aero compared to the FA car. So while the compound is R25B (hella soft by any measure) I can still run the entire season on them. I have confirmation from Hoosier that they're softer than the A7 compound. Did you say A6? That's a discontinued tire isn't it? When is the last time you drove on A6?
Lol. The Radical you mean clearly. Not the same. Not even worth addressing, and you know why. Did you really think you would sneak that by me?
Thunderhill is notoriously hard on tires. I have heard this from many regulars there. And I'm not even from the west coast. Lots of steady state turning as well. I can see you aren't paying attention to what I'm saying.
Sigh....... Nevermind mr tire czar, you may continue bemoaning people about the tires they put on their own cars based on your all encompassing bubble.
Last edited by heavychevy; 08-04-2018 at 04:25 PM.
"*I* do this with my [insert equipment here], and Racer X did this time there, and my time is only a little off THEREFORE your [argument] suck."
We've all done that. It's about as asinine as you can get between track people, and I find track people to be the most "A" type personalities that has to win every argument.
In reality.
There are a TON of variables. Unless you can provide data in a controlled environment to back up the claim, it's all MOOT. Temperature can have effect of SECONDS per lap. Tracks may have different configurations. Traffic, humidity, etc...even the tilt of Earth axis can have affect on any lap time, and we haven't even started on equipment.
But back on topic, there was this FANTASTIC discussion on another car forum that I can't for the life of me find, but it talks bout how as a driver approach the maximum slip angle of a tire, there's a small window where your fastest lap comes from. This might have been a Ross Bentley webinar that was recycled on the M3 forum, my memory is hazy in my advanced age. But the gist of it is, as you approach your fastest possible lap based on what the tire's maximum slip angle is, it's a bell curve in relationship to total amount of grip. Your fastest lap actually can come on either side of the top of the curve, either just shy of the optimum slip angle of the tires, or slightly OVER the optimum slip angle of tires.
The difference in amount of tire wear is insane though. If you can manage to just stay under the slip angle, and keep it there, your lap times are virtually the same as you driving at 11/10th and slightly past your optimum slip angle. Some of the empirical data shown that living on either side of max grip and optimum slip angle results in a tire life difference of 3-5x. Meaning if you're doing your fast laps on the other side of the bell curve, your tires will last only 1/3rd the time/distance as if you're living on the left side of the bell curve.
I have a few friends who has done multiple 25 hours of Thunderhill. They've managed to podium in their classes before, and the consensus is, that you can sacrifice a few tenth in lap time (on the original THill course) and extend brake and tire life SIGNIFICANTLY. We're talking about 1/2 second off qualifying pace. They said that in endurance racing you shoot for that sweet spot, not your fastest possible laps.
But the flip side of that coin. You can PUSH the car to a point where you're past the optimum slip angle, and you can LIVE there, and you'd be about the same 1/2 second off your qualifying pace, but you'd burn through a set of tires in a dozen lap. I've seen this. Guys that goes out there lap after lap going FLAT OUT and complain that their tires are toast in a couple of sessions. While I can probably go out do the same or nearly the same lap time, and have the same tires last half a dozen track days.
So what's my point? Back to bench racing. Just because *I* can make my tires last longer, doesn't mean I'm not "pushing." Again, variables. I can drive ***** out and destroy a set of tires in 1 day sliding through every turn. Or I can drive half a second off pace at HPDE (about 8/10th) and make the same tires last a season.
You'll find REALLY good drivers, people who are club racing level or above, to be able to control their tire wear nearly at will. I'm sorry, but anyone who argues that if you're not burning through a set of tires every x number of track days isn't pushing hard? Doesn't know what he/she's talking about.
This is the graph I'm talking about, but I still can't find the discussion. Again, the gist is, the difference in tire wear on the right side of the green curve, and the left side of the green curve, is HUGE.
"*I* do this with my [insert equipment here], and Racer X did this time there, and my time is only a little off THEREFORE your [argument] suck."
We've all done that. It's about as asinine as you can get between track people, and I find track people to be the most "A" type personalities that has to win every argument.
In reality.
There are a TON of variables. Unless you can provide data in a controlled environment to back up the claim, it's all MOOT. Temperature can have effect of SECONDS per lap. Tracks may have different configurations. Traffic, humidity, etc...even the tilt of Earth axis can have affect on any lap time, and we haven't even started on equipment.
But back on topic, there was this FANTASTIC discussion on another car forum that I can't for the life of me find, but it talks bout how as a driver approach the maximum slip angle of a tire, there's a small window where your fastest lap comes from. This might have been a Ross Bentley webinar that was recycled on the M3 forum, my memory is hazy in my advanced age. But the gist of it is, as you approach your fastest possible lap based on what the tire's maximum slip angle is, it's a bell curve in relationship to total amount of grip. Your fastest lap actually can come on either side of the top of the curve, either just shy of the optimum slip angle of the tires, or slightly OVER the optimum slip angle of tires.
The difference in amount of tire wear is insane though. If you can manage to just stay under the slip angle, and keep it there, your lap times are virtually the same as you driving at 11/10th and slightly past your optimum slip angle. Some of the empirical data shown that living on either side of max grip and optimum slip angle results in a tire life difference of 3-5x. Meaning if you're doing your fast laps on the other side of the bell curve, your tires will last only 1/3rd the time/distance as if you're living on the left side of the bell curve.
I have a few friends who has done multiple 25 hours of Thunderhill. They've managed to podium in their classes before, and the consensus is, that you can sacrifice a few tenth in lap time (on the original THill course) and extend brake and tire life SIGNIFICANTLY. We're talking about 1/2 second off qualifying pace. They said that in endurance racing you shoot for that sweet spot, not your fastest possible laps.
But the flip side of that coin. You can PUSH the car to a point where you're past the optimum slip angle, and you can LIVE there, and you'd be about the same 1/2 second off your qualifying pace, but you'd burn through a set of tires in a dozen lap. I've seen this. Guys that goes out there lap after lap going FLAT OUT and complain that their tires are toast in a couple of sessions. While I can probably go out do the same or nearly the same lap time, and have the same tires last half a dozen track days.
So what's my point? Back to bench racing. Just because *I* can make my tires last longer, doesn't mean I'm not "pushing." Again, variables. I can drive ***** out and destroy a set of tires in 1 day sliding through every turn. Or I can drive half a second off pace at HPDE (about 8/10th) and make the same tires last a season.
You'll find REALLY good drivers, people who are club racing level or above, to be able to control their tire wear nearly at will. I'm sorry, but anyone who argues that if you're not burning through a set of tires every x number of track days isn't pushing hard? Doesn't know what he/she's talking about.
This is the graph I'm talking about, but I still can't find the discussion. Again, the gist is, the difference in tire wear on the right side of the green curve, and the left side of the green curve, is HUGE.
I'll bite. This is a good beginning for a full theory. First I'd like to see the actual data for this claim "[s]ome of the empirical data shown that living on either side of max grip and optimum slip angle results in a tire life difference of 3-5x." Second, I'd like to see proof that the guy who chews up his cup 2's in 6 sessions drives "on the other side of the bell curve" where wear is exacerbated.
How else can I put this? Say we take the time for the best lap and we drive near it until the tires wear totally on the first side of the bell curve then we drive on a fresh set on the other side of the bell curve. If we measure tire wear and we get 5 sessions on the first set and 15 sessions on the other I'm still right and your theory is still right but heavychevy is still wrong.
Another weakness I see in this theory is that we're talking about road course. The car will be transitioning to various states of grip in every turn! This is not a skidpad where you get your slip angle and bang it all the way until you hit the cords. The car is going to be going through a lot of angles in every turn. In the road course world you will have a distribution of yellows greens and fuschias. Even if your theoretical 3 to 5x wear is true, in application optimizing your position on the curve may only net 50% increased tire wear.
The overall point, is that you can be fast and have extended tire wear. Which is what I said initially. And what has been proven already. And this theory doesn't even take into account the track surface. It's only focusing on how the car is driven and grip is used. That can change in the SAME DRIVER.
I have over driven some tires and ruined them, I've also gotten great life from them. It impossible to get the same tire wear at CMP as Road Atlanta. You just are being too stubborn to acknowledge that speed is not the only factor in longevity which is the false conclusion you jumped to when trying to tell a guy he's not fast enough to run Cups on his car based on how many days he got from them. So no, either way, you are wrong.
Just eat your words and be done with it. He's already closer to a pro in the same car than you are. Dealing with the same heat related issues. If anything he should be telling you what tires to drive on.
Last edited by heavychevy; 08-04-2018 at 06:00 PM.
Mine just melted and delaminated. I loved them, and would probably pay the steep price for them, if I wasn't worried about the tire coming apart. I got about 3 track days out of them.
But as far as wear goes, just the track you go to has a bigger effect that anything. My first day (slow) at MSR-C ate way more tire than ECR did 2 for days, and I bet I had 3-4x more track time at ECR than MSR in total. Same thing on a bike. I can maybe get 2 days out of tires at MSR. I can get 5 or 6 at ECR, depending on how long I go out for and weather (30 min sessions).
Edit: I also think it's pretty damn obvious pushing your tires too far and sliding all over the damn place will kill tires faster (and any semblance of good lap times).
Last edited by village idiot; 08-04-2018 at 07:31 PM.
I'll bite. This is a good beginning for a full theory. First I'd like to see the actual data for this claim "[s]ome of the empirical data shown that living on either side of max grip and optimum slip angle results in a tire life difference of 3-5x." Second, I'd like to see proof that the guy who chews up his cup 2's in 6 sessions drives "on the other side of the bell curve" where wear is exacerbated.
How else can I put this? Say we take the time for the best lap and we drive near it until the tires wear totally on the first side of the bell curve then we drive on a fresh set on the other side of the bell curve. If we measure tire wear and we get 5 sessions on the first set and 15 sessions on the other I'm still right and your theory is still right but heavychevy is still wrong.
Another weakness I see in this theory is that we're talking about road course. The car will be transitioning to various states of grip in every turn! This is not a skidpad where you get your slip angle and bang it all the way until you hit the cords. The car is going to be going through a lot of angles in every turn. In the road course world you will have a distribution of yellows greens and fuschias. Even if your theoretical 3 to 5x wear is true, in application optimizing your position on the curve may only net 50% increased tire wear.
Originally Posted by heavychevy
Right, so It's more likely a very soft compound though and hard one doesn't have enough grip to ruin itself so quickly. Hard compound tires when over driven tend to chunk and degrade but still remain in tact. So the treadwear rating is bogus and the softer compound is the reason for the shorter braking distances.
Today very soft Nascar rain tires were said to chunk from dry overheating. Is that a contradiction!?
If they lasted 6 track days while being drive 3,500 miles on the road they were simply not pushed. 3 track days is about the most you can get out of them if driven proper ~ 4 hours on the C7 Z06, and less on the ZR1.
You are probably better off with the Super Sport/4S if you get this much tire life out of Cup 2. That way you use a tire with a wider range of operation and the car is less prone to spinning out in the cold or in the wet.
I put the 4 S's on my Z51 after the first run-flats wore out. I agree - it is a great tire and it works really well in the Florida rain. Once the ZR1 gets here I will replace the Cup2's with this tire too when the time comes. But I'm not doing any track days so my 2-cents probably isn't appropriate for this thread :-)
Last edited by Repo Pilot; 08-09-2018 at 09:56 PM.
All four of my Cup 2 delaminated within 3700 miles and 3 or so DE events, just as Questar's and all the others, on the second band from the inside.
Michelin says they 'aren't aware of any issues with the Cup 2's. SMH.
You have a tire designed for track use, that fails under such use. How is that not an issue?
Thankfully Discount Tire replaced them all for $177 under their own warranty. They said they will not be doing that again since I track the car so often.
Now the OEM Cup 2's lasted 4 - 5 DE events and 4100 miles, but that was through cooler seasons.
I do agree that how smoothly you drive has as much if not a greater input on wear than lap times.
I put the 4 S's on my Z51 after the first run-flats wore out. I agree - it is a great tire and it works really well in the Florida rain. Once the ZR1 gets here I will replace the Cup2's with this tire too when the time comes. But I'm not doing any track days so my 2-cents probably isn't appropriate for this thread :-)
Your input is still relevant. Our OP drove 3,500 miles on the road on his track tires. The whole point of driving on stock street legal tires on track is to have a tire that can do it all. So when you judge it, it should be based on road manners as well.
I had one of the fastest guys who drives 'vettes in N. Cal. drive me on Thunderhill in his C7 Z06 on Super Sports. He was quicker than I was on Cup 2 by some margin. It shows that for most amateurs driving at HPDEs on street tires it's more about driver skill than anything. I say use a jack of all trades tire like 4S then skip straight to slicks. I used to like the Cup 2 but once I tried Corsas for the street and Hoosiers for the track I have to say, Cup 2 were a mistake. They are neither here or there. Terrible street tires with less grip than Corsas in just about any situation and terrible track tires, way slower than a 355 Hoosier S100 and way less durable.
Disclaimer, till this day I'm still the only one I know that drove the C7 Z 3 years street and track with no TC or AH. I presume my wear might be different since there is no computer aid to smooth my inputs.
Last edited by SBC_and_a_stick; 08-10-2018 at 01:33 PM.
Your input is still relevant. Our OP drove 3,500 miles on the road on his track tires. The whole point of driving on stock street legal tires on track is to have a tire that can do it all. So when you judge it, it should be based on road manners as well.
It may be your “whole point” but not necessarily everyone else’s. I don’t normally run Cup 2’s on the street, I run Super Sports. They are a great street tire (for me) but didn’t stand up too well on track (for me). The Cup 2’s will work (on street), on a warm sunny dry day and I several times used them to drive to and from the track when using my trailer wasn’t an option... that’s how they got the 3,000 to 3,500 miles on them over the year and a half I used them.
Where I live the cost of slicks is high. Scrubs are unavailable. Plus of course the expense of buying a set of quality 18” wheels to mount the slicks is also high. Even if Cup 2’s don’t last quite as long as slicks it’s still cheaper and easier to buy the Cup 2’s (in my location) than to use slicks. I don’t do enough track days to justify the costs on the slicks and wheels... not the costs in my area.
What works for you may not work for everyone else... certainly it’s not the same cost structure... not for me anyway.
08-03-2018, 11:56 PM
