GT3 Cup and Michelin slicks
04-03-2006, 05:06 PM
#16
Darth Cup
Rennlist Member
Rennlist Member
Join Date: Jun 2001
Location: Austin, TX
Posts: 824
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by AW
Kevin, I agree. I got one set of Michelin cup tires that had (for me) better performance than dunlop. There was no S7, S8, or S9 yellow sticker on them. Instead, there was a Yellow "Porsche CUP" sticker on the side. The 2 sets of S9 rears I got, in my experience were significantly slower. I will try and report on the S8.
Do you have any Michelin documentation about this SI tire compound?
Mike, yes this is very confusing. I spent thousands of dollars is poor tires and posted this thread to make sure everyone is informed. Do you have Michelin documentation showing that rear cup tires are S9 / hard? All the documentation I have (some of it posted here) represent cup tires as being medium/intermediate or S8
AW
Do you have any Michelin documentation about this SI tire compound?
Mike, yes this is very confusing. I spent thousands of dollars is poor tires and posted this thread to make sure everyone is informed. Do you have Michelin documentation showing that rear cup tires are S9 / hard? All the documentation I have (some of it posted here) represent cup tires as being medium/intermediate or S8
AW
BTW, I've been happy with just using the S7A/S8A on my Cup. Guess I'm not as fast a driver as Mike (I'm very impressed that you corded a tire in 6 sessions!
)
04-03-2006, 05:27 PM
#18
Rennlist Member
Call Bob Williams, JD Motorsports/Michelin racing manager. He works with the GT3 cup teams etc and I spent time with him in the Michelin trailer in Atlanta on Saturday. 864/525-7783
also see jdmotorsports.com for more info
Let us know what you find out!
also see jdmotorsports.com for more info
Let us know what you find out!
04-03-2006, 05:51 PM
#19
Pro
Thread Starter
Mike. I know and respect JD's position. But at the end of the day, I only believe Michelin's official documentation. I have yet to see any Michelin publication describing cup tires as hard compound.
If you like your S9 tires, I'm happy for you and you should keep buying them. Me, I'm only running "Porsche CUP" or S8A labeled tires moving forward.
AW
If you like your S9 tires, I'm happy for you and you should keep buying them. Me, I'm only running "Porsche CUP" or S8A labeled tires moving forward.
AW
04-03-2006, 06:34 PM
#20
Addict
Rennlist Member
Rennlist Member
Join Date: Dec 2001
Location: SF bay area, CA
Posts: 2,094
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by AW
I decided to skip at the last minute because of the predicted heavy rains. I still don't have rain tires...
AW
AW
04-03-2006, 07:02 PM
#21
Nordschleife Master
Join Date: Oct 2004
Location: Vacuuming Cal Speedway
Posts: 7,306
Likes: 0
Received 7 Likes
on
5 Posts
Great topic, sorry I'm late to the party.
Here's what I've been told: The Yellow stamped Cup tires, as specified for the IMSA series, are the same compound on the ground as the 7A fronts and 8A rears (I've never seen a 9A tire). The difference is in the sidewalls as the Supercup series is run on heavily banked tracks so the sidewalls are built stronger. I've run through 2 sets of the Yellow stamped set, and 3 sets of 7A/8A's and I can't tell a performance difference. I will say however, the Yellow stamped sets did last longer. I ran one of them through 14 cycles, while the non-stamped sets usually quit around 6-8 cycles. The price difference is significant, $324. more for the yellow cup tire set. At Cal Speedway with PCA 2 weeks ago, I was garaged next to a very experienced driver with a 997 Cup. He ran a set of the 7A/8A's and separated them at the shoulder of his right rear on the 3rd. cycle. Track is heavily banked and runs CCW. He throws the car around alot and probably could have used the stronger shoulder. He was pissed at Michelin for selling him those tires in lieu of the Yellow set. There is a new tire coming out this month for the 997 Cups, and it will be stamped and called the Green set.
That's what I know.....
Here's what I've been told: The Yellow stamped Cup tires, as specified for the IMSA series, are the same compound on the ground as the 7A fronts and 8A rears (I've never seen a 9A tire). The difference is in the sidewalls as the Supercup series is run on heavily banked tracks so the sidewalls are built stronger. I've run through 2 sets of the Yellow stamped set, and 3 sets of 7A/8A's and I can't tell a performance difference. I will say however, the Yellow stamped sets did last longer. I ran one of them through 14 cycles, while the non-stamped sets usually quit around 6-8 cycles. The price difference is significant, $324. more for the yellow cup tire set. At Cal Speedway with PCA 2 weeks ago, I was garaged next to a very experienced driver with a 997 Cup. He ran a set of the 7A/8A's and separated them at the shoulder of his right rear on the 3rd. cycle. Track is heavily banked and runs CCW. He throws the car around alot and probably could have used the stronger shoulder. He was pissed at Michelin for selling him those tires in lieu of the Yellow set. There is a new tire coming out this month for the 997 Cups, and it will be stamped and called the Green set.
That's what I know.....
04-03-2006, 07:10 PM
#22
Nordschleife Master
Join Date: Oct 2004
Location: Vacuuming Cal Speedway
Posts: 7,306
Likes: 0
Received 7 Likes
on
5 Posts
AW bye the bye....
My wrench has been trying to get me to try the Yokohamas. They require a different setup than the Michelins, specifically less camber as they are harder (maybe that's what's wrong with those 9A'S). I did try a set with my Michelin setup (neg. 4.5 front/4.0 rear), and they were slower. I mention this because the fastest Cup car out of 10 at Cal Speedway was running the Yokos and we discussed his setup. He agreed that the Michelins were a better tire for the GT3 Cup, but that with proper setup the Yoko's were damn close. He was running neg. 3.9 front/ and 3.0 rear if I remember correctly. I'm going to change my setting and give them a try at WSIR in a few weeks at the next POC race.
I'll post me thoughts....
My wrench has been trying to get me to try the Yokohamas. They require a different setup than the Michelins, specifically less camber as they are harder (maybe that's what's wrong with those 9A'S). I did try a set with my Michelin setup (neg. 4.5 front/4.0 rear), and they were slower. I mention this because the fastest Cup car out of 10 at Cal Speedway was running the Yokos and we discussed his setup. He agreed that the Michelins were a better tire for the GT3 Cup, but that with proper setup the Yoko's were damn close. He was running neg. 3.9 front/ and 3.0 rear if I remember correctly. I'm going to change my setting and give them a try at WSIR in a few weeks at the next POC race.
I'll post me thoughts....
04-03-2006, 07:31 PM
#23
Pro
Join Date: Mar 2004
Location: SoCal
Posts: 744
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by jrgordonsenior
Great topic, sorry I'm late to the party.
Here's what I've been told: The Yellow stamped Cup tires, as specified for the IMSA series, are the same compound on the ground as the 7A fronts and 8A rears (I've never seen a 9A tire). The difference is in the sidewalls as the Supercup series is run on heavily banked tracks so the sidewalls are built stronger. I've run through 2 sets of the Yellow stamped set, and 3 sets of 7A/8A's and I can't tell a performance difference. I will say however, the Yellow stamped sets did last longer. I ran one of them through 14 cycles, while the non-stamped sets usually quit around 6-8 cycles. The price difference is significant, $324. more for the yellow cup tire set. At Cal Speedway with PCA 2 weeks ago, I was garaged next to a very experienced driver with a 997 Cup. He ran a set of the 7A/8A's and separated them at the shoulder of his right rear on the 3rd. cycle. Track is heavily banked and runs CCW. He throws the car around alot and probably could have used the stronger shoulder. He was pissed at Michelin for selling him those tires in lieu of the Yellow set. There is a new tire coming out this month for the 997 Cups, and it will be stamped and called the Green set.
That's what I know.....
Here's what I've been told: The Yellow stamped Cup tires, as specified for the IMSA series, are the same compound on the ground as the 7A fronts and 8A rears (I've never seen a 9A tire). The difference is in the sidewalls as the Supercup series is run on heavily banked tracks so the sidewalls are built stronger. I've run through 2 sets of the Yellow stamped set, and 3 sets of 7A/8A's and I can't tell a performance difference. I will say however, the Yellow stamped sets did last longer. I ran one of them through 14 cycles, while the non-stamped sets usually quit around 6-8 cycles. The price difference is significant, $324. more for the yellow cup tire set. At Cal Speedway with PCA 2 weeks ago, I was garaged next to a very experienced driver with a 997 Cup. He ran a set of the 7A/8A's and separated them at the shoulder of his right rear on the 3rd. cycle. Track is heavily banked and runs CCW. He throws the car around alot and probably could have used the stronger shoulder. He was pissed at Michelin for selling him those tires in lieu of the Yellow set. There is a new tire coming out this month for the 997 Cups, and it will be stamped and called the Green set.
That's what I know.....
So what do you think of that?
-Kevin
04-03-2006, 07:41 PM
#24
Pro
Thread Starter
JR, 7a front 8a rear is my conclusion as well. The stiffer sidewall on cup tires makes sense too. It would still be good to see an actual Michelin doc on the subject.
About non-michelin tires, I tried both Yokohama and Dunlops. I had better results with dunlops but the life was kind of short (6-7 cycles). The allignment is definitely very different from Michelin, (ride height, camber and toe if I remember correctly). I did not have much luck with Yokos but when I tried them I had other issues with the car so I'm not sure...
Apparently, the best tire choice for our GT3 Cup is real, yellow labeled "Porsche CUP" Michelin slicks. Performance is better than dunlops and they last longer.
I'm glad I'm not the only one going crazy over these Michelin S7, S8, Cup and S9 labels. What a mess!
AW
About non-michelin tires, I tried both Yokohama and Dunlops. I had better results with dunlops but the life was kind of short (6-7 cycles). The allignment is definitely very different from Michelin, (ride height, camber and toe if I remember correctly). I did not have much luck with Yokos but when I tried them I had other issues with the car so I'm not sure...
Apparently, the best tire choice for our GT3 Cup is real, yellow labeled "Porsche CUP" Michelin slicks. Performance is better than dunlops and they last longer.
I'm glad I'm not the only one going crazy over these Michelin S7, S8, Cup and S9 labels. What a mess!
AW
04-03-2006, 08:07 PM
#25
Arnaud, The 8a has a stiffer sidewall and harder compound and is a better tire. Also says Porsche Cup in yellow on it. The others are very quick as they have a softer compound but are not as stiff. Yokes roll over when pressed but are quick when driven smoothly. Dunlops are a bit stiffer than the Yokes, also quick but tend to go away a bit quicker as far as grip. My choices are in this order, Michelin(Porsche Cup), Michelin regular lets call them, Dunlops, Yokes.
Best, hope all is well.
G
Best, hope all is well.
G
04-04-2006, 05:02 AM
#26
Drifting
Join Date: Dec 2004
Location: Munich
Posts: 2,722
Likes: 0
Received 0 Likes
on
0 Posts
to add to the difficulties in choosing which 'Cup' tyres - they vary from season to season. So one season you might have a tyre with less initial grip than previously but is better through the duration of a Supercup sprint race, or one which is great for one fast qualification lap and then deteriorates quickly during the race.
Michelin and PAG play around with this from season to season.
R+C
Michelin and PAG play around with this from season to season.
R+C
04-04-2006, 11:55 AM
#27
Pro
Thread Starter
Glen, from everything we know, the 8A is a tire with a yellow "8a" label and is not a cup tire. The one with a stiffer sidewall is the one with a "Porsche CUP" yellow label. I believe this tires uses an 8A compound as well because it is documented as such by Michelin, but some here believe it is an 9A hard compound or even a different compound. Further 8A refers to a medium compound.
RC are you implying that Porsche and Michelin change the tires on purpose or is it that batches are somewhat inconsistent?
AW
RC are you implying that Porsche and Michelin change the tires on purpose or is it that batches are somewhat inconsistent?
AW
04-04-2006, 08:41 PM
#29
It sounds like most of you guys are driving cup cars.
My question is what tire do you think would be best for my 993 light weight race car (2,280# with driver) Michelins or Dunlops?
Any advice here would be greatly appreciated
My question is what tire do you think would be best for my 993 light weight race car (2,280# with driver) Michelins or Dunlops?
Any advice here would be greatly appreciated
04-04-2006, 08:59 PM
#30
Pro
Thread Starter
You can probably get both Michelin and Dunlops to work on your car but you'll have to find the right allignment for each. With slicks, the only way to go is to use a pyrometer after 5 hot laps to really make sure your setup is appropriate. You will also have to select the compound for both Michelin and Dunlops. In general, on a 911 the front compound is softer than the rear.
Our cup cars are optimized for slicks. But with a light weight 993, I would seriously consider running Michelin Sport Cups or hoosiers. Slicks are very expensive (from $1200 to $1600 a set) and only last for an average of 10 heat cycles.
Some people at PRC run some light 911 with some goodyear slicks (GTL class I believe). They claim the tires last a lot longer than one weekend. You may want to look into that alternative. www.porscheracingclub.com
AW
AW
Our cup cars are optimized for slicks. But with a light weight 993, I would seriously consider running Michelin Sport Cups or hoosiers. Slicks are very expensive (from $1200 to $1600 a set) and only last for an average of 10 heat cycles.
Some people at PRC run some light 911 with some goodyear slicks (GTL class I believe). They claim the tires last a lot longer than one weekend. You may want to look into that alternative. www.porscheracingclub.com
AW
AW