fryd

Hearing Yellows are for 996 Cups and Blues are for 997 Cups. That correct? I'm seeing Blues at $1,930 +tax, shipping, etc. per set. Ouch!

Geoffrey

Yellows are simply an older verion of the "Cup" tire. It has been my experience that the Blues are a better tire initially, and they perform better over more heat cycles. The thing I like about the Blues is that they have a protection rib on the outside. I've always said that the Blues are like magic. The Yellow tire is a good tire and far better than the S7 / S8 "customer" tire which is awful.

fryd

Thanks Geoffrey...to be clear then, the Yellows will work for a 997, but just not as optimally as the Blues?

Apex GT

I concur with Geoffrey.
Yellows are also cheaper and therefore you can buy more

Geoffrey

Yes, the Yellow are the same size and will work fine.

fryd

Awesome! thanks.

Accelerator

What problems did you find with the S7/S8 tires? I'm on my second set and find they're really slippery when cold and take a long time to build heat. Traction under acceleration doesn't appear to be as good as the Hoosier R6's I ran before.

PatK-Mpls

The yellows and the blues are nearly the same tire. The blues have a reinforced shoulder that enables the tire to holdup better. Lap times between the two are very similar. However, the yellows are prone to catostrophic failure when used with high camber setups.

Geoffrey

I found the S7/S8 tires wouldn't take much camber and tended to grain which caused them to be slippery, especially in the rear. The sidewall also seemed too soft.

PatK-Mpls

Just to tease the discussion: The newest compound (greens) are a different compound and construction and (apparently) quite a bit quicker.

Alas, they are not being imported and currently only being used for Supercup and C Cup.

Geoffery- Completely agree with your observations but I never got graining - they just let go and separated at the shoulder. In fact, the camber limit introduced mid-season in 2006 IMSA was a direct response to failures.

Geoffrey

Interesting about the separation problem. My car is 2200lbs, so perhaps the lighter weight helped me to avoid that issue.

fryd

OK..you've got me worried. What was the limit they introduced?

Geoffrey

He is talking about the S7/S8 tire which isn't produced in Cup sizes any longer, so no worries...

Accelerator

That's scary. My first set separated at the left inside shoulder at the rear. I just assumed something cut the tire down. Maybe that wasn't the case. Grid weight of my car is 3470 with considerably more downforce than a normal 996tt. I talked to a Michelin tech before I ever purchased the tires with concern that they would accommodate that kind of weight and he said not to worry that many Vipers ran those sizes. Rear camber at the time was 3.4/3.3.

Actually there are some S8's in a cup size--24/64R 18 but they don't make the 68.

Geoffrey

There is also a 31/71 S8 which seems to work well on GT3RSRs and Big turbo cars. I am only specifically talking about the Cup sizes in S7/S8.