Anthony F

Glad to see someone else running these tires.

6T2Vette

I read CR6-ZZ Avons are exempt for use on cars before 1990. I guess they're not legal on 1990's and later.
Bob

68hemi

What do you mean by exempt. If they are DOT approved they are legal.

SWCDuke

I believe that's a European requirement, not USA. A US DOT legal road tire is legal for any car regardless of year.

Duke

69ttop502

Treadwear is 80. Like said above, if they last 10-15000 miles, that is years on my car so despite expense, it is worth it. Yes they are sticky. Just rolling around in the garage and driveway, amazing what they pick up lol. My thinking is, to get the great tires in 17 and up inch sizes, I would need new wheels too, so it wasn’t out of line to go for these tires. And I am one of those guys that just prefers the look of 15’s on these cars!

SWCDuke

A WARNING TO ALL! The 215/70R-15 will likely not fit C2s without shaving the fender lips. The 205/70 and 215/70 15" sizes are within about 0.1-0.2" OD and therefore revs/mile, but the 215/70 has nearly an inch wider tread. Also the revs/mile specs appear to be the "rigid body" calculation based on inflated OD, not the actual measured loaded revs/mile from actual measurements on a tire dynamometer. Multiply their values by 0.97 to get an approximation of actual loaded revs/mile. For reference OE 6.70-15s are 760 and 7.75-15s are 775. Speedometer differences with either size should be marginal.

Go to the Roger Kraus Racing or Avon Web site, download CR6ZZ spec sheet pdf and carefully review it before you buy.

Duke

6T2Vette

Yes, I would strongly recommend talking to Roger Krauss himself. He helped me select the tires I bought. I believe he told me he had raced C1's himself. I wanted a tire with an 8" tread in the back but I opted for the 225/65 which has tread of 7.2". It has a diameter of 26.7" and a section of 9.1". By comparison the 215/70r15 has a diameter of 26.7", tread of 6.9", and a section of 9.0". This is using a 6.5" rim.
So I felt I was getting a 0.3" wider tread with only a 0.1 increase in the section diameter.
Bob

jerry gollnick

I wonder how they would do in the rain? No side skipes? Duke used to swear by a particular tire for our old C1 and C2s. i don't remember what it was , name began with a V as i recall.
I vintage raced for 20 years and sticky tires are great on the track but boy they pick up ALL kinds of stuff and get embedded with sand and small rocks. They throw bigger rocks up in the wheel wells. I want to go with a harder compound for the street.

68hemi

I did not realize they are THAT sticky. Anyone know what the next best speed rated radial tire is that is a little harder? I was planning on replacing my 205/70 x 15s with the Avons but may re-think it as all of my driving is street but often spirited and with curvy mountain roads.

GUSTO14

Would it be the Vredestein Sprint Classic by chance? They do have a couple in the 15" size that might work on the C1 & C2's
https://www.tirerack.com/tires/tires...Sprint+Classic

They appear to be made in Holland.

GUSTO

SWC Tim

From experience, they are sticky but not to the point that you would be unhappy with them. Actually if you do spirited driving you would love them. I have been surprised how well they perform in the rain. Wet braking, better than the old Firestone radials I replaced with the Avons.
SWC Tim

SWCDuke

Based on my experience with several different brands/models of DOT legal racing tires, their optimum tread temperature for maximum grip is in the 180-200F range. At those temperatures the tread is as sticky as fly paper, and they will pick up debris, but there's no way you can achieve this tread temperature range in any kind or sane public road driving. They still have way more grip than common tires at normal road speeds, but they shouldn't pick up debris like a hot racing tire.

Siping, the narrow slits you see in all season tires, are primarily for snow traction. Look at any serious summer high performance tires and these are absent. The CR6ZZ has plenty of water evacuating grooving to be safe to drive in the rain, but be cautious.

Also, DOT legal racing tires and summer high performance tires have a fairly high "glass transition temperature", which is the temperature that the compound suddenly hardens and the tires can become slippery. It's usually in the range of 30-40F degrees. Toyo warns not to drive their Proxes RA1 at less than about 40 degrees as it may cause tread cracking.

The next best alternative to the CR6ZZ is probably the Vredestein Sprint Classic, made in The Netherlands and very popular in Europe on vintage sports cars. It's available in a 215/70R-15 either H or V-rated. I can't remember which. An easy Web search will reveal more info and retailers.

Duke