Ecsta XS vs. R1R

OK, so I need tires for my '94 Vette, new to me, and it takes an unusual size. I do around 125 - 150 track miles per year, plus around 3500 street miles, and I want to run the same tires - no desire to have a dedicated set of track wheels and tires, been there, done that many, many times. So a few questions:

Any comments on the streetability of these two? Has anyone heard whether there's a new kumho replacement for the Xs in the pipeline for this year? Tread life in real world driving (I drive pretty gently on the street, and I'm certainly not looking for high mileage in this application, just looking for comparative info? I've always liked how Kumhos feel, but have no experience with the XS,and no experience with the Toyo. Comments, please.

Any other suggestions in a 285/40-17 and 255/45-17 or adjacent sizes? National Council of Corvette Clubs requires tires within 10 mm section width of stock for their stock classes, so I could go 275/40 on the rear and 245 on the front, but there still aren't a lot of tires available in these sizes. Who'd have thunk that 17s would be too small diameter for good selection in Vette sizes?

The XS is a fair weather friend. On a warm, dry day they are terrific. In cold and/or wet conditions the limits are sudden and unpredictable. Kumho's replacement (dubbed the V720 I think) won't be here until next year.

No experience with the R1R.

R1R takes little heat to grip, but can be overheated in hot conditions, which means spraying them down during summer months in between runs.

They're great on the road though.

From reviews of the XS it seems that it's generally not a great tire unless you're deep in a corner. I've heard they feel almost like bias plys in terms of squirmyness.

I found the XS's were fine for auto-x and daily driving. They took a decent amount of abuse at the track too.

Mine lasted through a 20 event + 5 lapping day season.

That said, they're not the best in the wet.

I was debating going with the Hankook RS3s as replacements but ended up going a step further with Nitto NT01s.

as big/heavy as the Vette is ... the R1R probably won't get the job done ... they become over-heated and greasy on my CRX in a lap or two .... great grip when cool .... lousy when hot ...

I was at CMP this past weekend with the muscle car brigade ( Detroit Speed ) ...with them was the BFG truck and their engineers .... they were trying to burn down a set of Rival's on a 600 hp Camaro ... couldn't do it ... from all the reports it's made with unicorn pee, pixie dust, and other magical mystery materials ..

even for my car it may be the tire of the future, but for sure for yours ( oh and they were running extremely quick times )

Dunlop Star Specs?

no longer being made ... the replacement is the ZII ... right now it's a toss up as to which will come out on top ... plus there's the new Bridgestone RE11a ... but right now, with what I saw at the track, my bet is on the Rival

not sure what the NCCC rules are on wheels, but 9.5" wide wheels were an option for the front. They came with the better suspension pkgs. Pre LT1 cars had them too. They should bolt right up to your base model without an issue. Now you can run 285 all around....

Agree with the statements above. The XS needs heat and dry, it's definitely not happy in the cold. The R1R turns to grease at GJMS under the Targa Miata after about 2 laps, but they're excellent in cool and very wet weather. If those are your only two options and given where you live, I'd run the R1R. But I'd rather see you on Dunlop ZIIs if you can manage the sizes.

Keith Tanner wrote: Agree with the statements above. The XS needs heat and dry, it's definitely not happy in the cold. The R1R turns to grease at GJMS under the Targa Miata after about 2 laps, but they're excellent in cool and very wet weather. If those are your only two options and given where you live, I'd run the R1R. But I'd rather see you on Dunlop ZIIs if you can manage the sizes.

I also vote ZII. It's kinda the best of both tires (R1R and XS).

Thanks, Keith,because I know you have been running R1Rs I was just going to email you directly after checking response to this topic, now I don't have to.

The problem, of course, is that I'm limited to something between 245 and 265 on the front to stay in NCCC stock (which isn't hyper critical, as most of the time I run for fun at GJMS, our local excellent Kart track and we don't got no steenkin' classes), and 275 - 295 in the rear, and the 94 LT1 came with 8.5 on the front and 9.5 on the rear, and I don't want to buy more wheels, as between summer and winter sets for the two 4WDs and the MR2 (which may be for sale in a couple of months) I've got stacks and stacks of the things. And while the dunlops and the rivals would be my first choice, they don't come in sizes suitable for the rear. Most manufacturers stop around 245 or 255 these days. I'm OK for now but will continue to appreciate the input.

Any other C4 guys out there? What do you use?

if you can afford to wait, then the Rival's could still be your best bet .... as the yr progresses the size selection will increase , I'm sure there are some on here that can find the anticipated size listing .... but yeah, good choice on the ZII