"The Direzza ZII still posed a lap time better by over 2/10s on a short 29-second course! The Direzza also had the best slalom time, tied with the Rival for first in average cornering, and came in second in stopping distance in the dry. It also beat the Rival in the wet."

http://www.onehotlap.com/2013/07/bre...acks-2013.html

 

I'm kinda happy the Rival doesn't come in the size I run. It keeps me from having to do tire testing

 

0.4% quicker in the dry and 1.6% slower in the wet vs. the Yok AD08. No info on how they stand up to heat which was the Star Spec's short coming.

Those margins in that size on those cars on that course with those drivers on that day are way short of declaring any of the four the outright winner.

 

It is certainly ONE of the fastest, and I personally think it is a great choice for dual duty as my experience suggests it loses less grip in the cold and wet than some of the other top autocross tires.

Cheers,

Charlie

 

Where are you headed next year, Charlie?

 

Probably the funny farm - either RTF or STF - oh wait! Street Stock? HS?

I guess I'll wait and see...

Cheers,

Charlie

 

There are added comments on linked pages from the OP post that say that the Rival is fastest on the track (take it with a grain of salt) and that the Rival is easy to drive fast to almost the limit, but at the limit the ZII is probably better. It is also noted that the Rival has 7.2/32 tread depth vs the 8 or 9/32 (depending on size) for the ZII. With less tread the ZII might easily out handle the Rival.

The Tirerack test (http://www.tirerack.com/tires/tests/...y.jsp?ttid=172) is interesting in how close these tires all are. Also how great the AD08R is, but at a 180 wear rating it won't be legal for Solo.

The only problem with just jumping on a set of ZIIs is the chunking that the ZIs did when they get heated on the track - I've got 2 sets that are dying of chunkitist.

However, for a great all around track, solo, rain, street tire at a reasonable price it looks like the ZII is hard to beat.

 

The Rival was also 1% faster than the ZII in the dry per the Grassroots magazine test with Andy Hollis and an ST Civic. As for that 200 number, check out Hankook's new rating on the R-S3.

I wouldn't throw away a gift set of 205/50-15 ZII's, Rivals, or RE-11a's.

 

I think it will be interesting to see how each tire does at Nationals this year.

Please do report how you like your tire choice whatever you pick.

Tire tests are only one measure. Real experiences count more.

 

Eddie,

The ZII's will chunk under heat as well. My last weekend resulted in significant chunking and now has me looking at R-compound tires.

I think the air temp was around 85 or 90, not sure on track temp, but it was apparently too much for them.

 

There are a lot of high performance summer tires that will chunk on the track if they are not shaved first.

 

That is too bad.

Will a short run on the track to heat cycle the tire help with this problem?

The AD08s I had were fantastic on the track and they are probably still the best all around tire, but they are expensive and they don't meet the 200 wear limit (rated 180).

I am still looking at the ZIIs as a rain track tire and for AutoX.

 

I doubt a heat cycle will solve the problem. This set of tires already had 2 or 3 days of track wear on them in much cooler conditions.

It was explained to me that I either needed to get them shaved or move up to an R compound tire.

 

I wonder if this is a Dunlop tire thing as the Z1s would chunk too but other tires like the RE11s and AD08s didn't.

With that said, now I wonder how the Rivals will do on the track. They already start out with less tread than any other tire out there.

 

Eddie, it's a compound thing. Grip in cool temperatures means poor heat tolerance. When the temps are 80F or higher I double spray my Star Specs after each autocross run including the first. Otherwise they become very hot and lose grip by the third run.

 

Sounds like save these tires for driving to the track and rain days.

 

Novice here, but very interested and have had chunking problems. What do you spray the tires with?

 

just regular old water. Pick up a water sprayer from Lowes/HD that they use to spray chemicals on lawns. Get a NEW one. Don't want to go spraying pesticides on your tires

 

Thanks! Another goodie to drop in my bag!

 

Ah reminds me of my chemistry days in school! :D fun times. As far as I know water is the ideal liquid to perform such a procedure due to its specific heat. Does anyone know of a better liquid?

 

It was a hot and steamy 2 days at Watkins Glen and the ZIIs performed very well on a BMW 328i running in the A-Solo group. No chunking. It may just have to do with how hard the tires are pushed and how balanced the car is.

 

Just read a comparison in the latest GRMS between the Z2S, Rivals and the R1R (as the baseline) using Whitier's STS Civic on a concrete Autocross course.

The Rival came out on top...the could not heap enough praise on it.

 

I've had Z2s, RS3s, Z1s, and have driven a car with Rivals on it. I think for overall performance, Z2s are what I'll be going with. Rivals probably have just a little more blunt grip than Z2s, but Z2s definitely perform better in the cold. For auto-x, I think it's well suited, esp since you can spray down tires between runs. Z2s also wear out a lot faster when they're hot. For track, I'd probably go with Rivals, or maybe even RS3s.. can't wait to see what hankook comes out with next though