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What's the Difference Between GT-O and GT-R Compound Contis?

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Looking at buying a set of Conti scrubs. What's the difference between the GT-O and GT-R compound, and where/why would one compound be preferable over the other? Thanks!


Because racecar.
Arizona, USA
I had the same question. YellowBoss and Cloud9 helped me out as per below:


I'm considering doing a different race class where I can run a full-on slick. I see Hoosier still has a ton (331 tires) of 285/645/18s left in GT-O spec.

Do you guys know what the actual differences between the Oval Spec and the normal "EC-DR"/"GT-R" spec are? Do you think these tires will be at a disadvantage on a straight-up road course?

A set of these would be $764 + shipping vs. $1400 for a set of 275 Hoosier DOTs.

I might have some stiff competition in the class I'd end up running but that's my decision to make.

Your thoughts on the tires?
From YellowBoss:
I posted in one of the threads about this. The GT-O is equal or close to the 275 CTSSC new I (Indy) compound. It is a little softer then last years 275 to handle Indy and places like Kansas so it does not heat up and blister. At Daytona it was not a problem because the banking is so steep you can run flat out.

I have used last years 275 compound with the GT-O 285's and this years Indy compound 275 tires and can not even feel the difference. I doubt all but the best drivers out there would be able to tell the difference. Even Jon told me he has mixed tires for practice and the drivers don't know.

The GT-R is Rolex for road course and I'm not sure of the exact compound but again it is so slight I doubt you would know if if you have the tires not different front and back but also left and right.

From Cloud9:
I've been running Conti slicks new GT-Os and takeoff GT-Is. I ordered a set of brand new R6s for the Mustang Roundup if that tells you anything ;) Now, in a race environment you might be better off with a slick for its endurance, but to put down one hot lap go with R6s.

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