kedvesh

Because of work, my Nitto 555RII DOT-Rs (manuf. Nov 2011; mounted Jul 2012) have not seen any normal road or high-speed track use since a weekend of fun at Road America in Aug 2012. They've simply sat mounted on stock C5Z06 wheels on my tire trailer under a tarp in my garage.

The tread on the fronts is above the wear bars; the rears are well past the wear bars with minimal tread and would definitely not pass a state vehicle registration safety inspection. I also have stock C5 coupe wheels shod with brand new (2015) all season tires for normal street (and possible wet weather track) driving.

Something else I have to consider--it seems many organizations are enforcing a 'no tire older than 5 years from manufacture' rule. So, 2016 may be the last year I can use my Nittos on the track.

Question to you drivers/users--and solely based on the use history and overly basic tire condition information I've given--do you think I can go out and still push my DOT-Rs until they cord or should I get new DOT-Rs or some decent summer tires (such as Conti DWs) for my C5Z06 wheels, reserving my stock coupe wheels w/ AS tread for colder, wetter weather?

Thanks in advance for the advice!

63Corvette

Just my opinion.....................
A) If you are just doing track days and not competition for speed, then "warm them up" and use them.
B) If you are going for speed or wins then get new tires.
C) However, I would recommend "NEWER" race tires (R-comps or slicks) from Forum Vendor GT RAcing Tires (http://gttrackdays.com/). They have tires from $50ea to $200 ea, and some are mounted and used, but they may have tires which have only been mounted. they are good people with a really great deeal on tires

Conesmacker

My opinion (based on 15 years of autocrossing & hi perf tires) is that sure.. you can trackday / solo these older tires...but they won't grip like when new, and would not be as 'safe'.

Trackday safety can be a bit of an oxymoron...obviously the safest thing is "don't set foot on a track", but since we're on this site, we're obviously looking more for fun than safety, so lower levels of safety become acceptable.

I would try to get all my money's worth and run them until I felt unsafe...which may or may not be down to the cords. It all depends on how those rears feel in corners at speed & under heavy acceleration.

I'd try them on a track day..but be prepared to kiss that entry fee good-by if you get out on the track and the tires never hooking up and it feels unsafe/unpredictable to you. If that happens, you have to consider your personal safety and safety of those also on track and make the decision to stay out on track, or pack it in and go home for the day.

Maybe try them at a safer venue first - a local solo / autocross which would be a much cheaper entry fee, and only top of 2nd gear speeds. This would be a test to see if the tires ever start feeling right to you in a probably safer environment.

Did the Nittos sit in a garage where they experienced multiple below freezing temperature events? That heat/cold cycling makes the rubber harder / less grippy.

froggy47

According to a tech I spoke with at Hoosier, true slicks & dot-r slicks have about a 2 year shelf life. They (Hoosier & others) do not add certain preservatives to the compound which the do add to street tires. This is part of why they work so well (when they are new).

Many of these do not have build dates. Some do.

I would use them for autox, but stay off tracks.

IMO

brkntrxn

I agree with the above statements since they are Nittos. If they were Hoosiers, I would recommend throwing them in the trash as they would be dangerous. I have personally witnessed more than a few old Hoosiers come apart at speed and damage a car.

Since those are Nittos, you will most likely be fine. Just don't expect them to grip as well as you would think.

froggy47

A "funny" thing happened on the freeway today & in a round about way relates to the thread so I'll share. Small suv is in the number 1 lane about 4-6 car lengths ahead of me, I'm number 2 lane and we are both doing about 80 mph going with the flow.

In the blink of an eye I see that one of his left tires has departed from it's wheel, still in a perfect circle, and is now between him & me all of us now at maybe 70 mph.

He/she does a very neat job of moving into the freeway center breakdown lane (which is luckily about 1 car width wide), not hitting the brakes and I now see in the driver door mirror the suv coasting to a stop in the breakdown lane.

In my right door mirror I see the tire crossing all the lanes of traffic (medium to heavy) and ending up in the right freeway ditch, some luck and some swerving result in it's unimpeded trip.

I spend a moment feeling for the poor sucker who is now stopped in that narrow lane as cars fly by and I hope he has the sense to dial a wrecker & assume a defensive position (as he can) and wait.

Having had my share of flats, blowouts, etc. my guess is that maybe he had a space saver wheel on and was exceeding its speed/mileage parameters, but that's only a guess. Just weird to see one come off in a perfect circle like that.

Hope he's ok.

Moral of the story is, I guess, have good tires.

CHJ In Virginia

Way too old - get rid of them. Measure the cost of your car - and you against the cost of new tires or scrubs ! Serious loads on tires even running HPDE, not worth the marginal savings trying to run old worn tires.

kedvesh

Thanks for the comments and thoughts thus far!

I wanted (and still want) to get my money out of these tires (or any tire). I don't necessarily want to trash $1100. But all-in-all, that's a lot less than potential body work or buying another 'Vette (new or used) if one of the tires lets go. The Corvette/track tax strikes again, I guess. Sucks to be me.

To color my hesitation on continuing to use these "old" DOT-Rs, a number of years ago and pre-DOT-R, I was using some 2-yr old, half-worn Goodyear Supercars at Sebring and experienced a bad spin in T17; reference (Not me BTW )--
'Vette was o.k., but I called it a weekend with half a Sunday remaining and drove 900 miles home. I partially chalked the spin up to a number of driver factors, but the tires had more than a few street-track-street-track cycles. Post-event research on tire age certainly didn't help my post-spin attitude on the GYSCs after finding a negative reputation after half worn...darn things never saw a road course again. The last straw before I got rid of them was their lack of wet weather street capability after half worn. Ugh.

FYI, the garage where I keep my 'Vette and the tires is attached to the house. It never gets down into freezing temp territory, but it does get mighty chilly sometimes.

O.k. If I ditch my current DOT-Rs, out of the current crop of street and/or DOT-Rs, what brand/model would y'all recommend for my stock C5Z06 rims, either formulation? From 2008 onwards, I've been trailering the Z06 wheels w/ DOT-Rs to the track behind my 'Vette, using my stock coupe wheels for street/highway and wet weather track driving. (Can't seem to find any Nitto NT 555RIIs...plenty of the drag version 555Rs though. For streets, leaning towards Continental ExtremeContact DW; would love to try the Michelin Super Sport, but they don't make it in 265 or 275/40-17 for my front rims.)


Thanks!

froggy47

IIWM I'd try these out

http://www.tirerack.com/tires/tires....-Force+Rival+S

They have some big sizes unlike other ultra high performance summer tires.



Don't get hung up over the DOT-R label, street tires have come a long way.

kedvesh