Besides some track and street time they have been well cared for. They look great, no checking/cracking or dry rot at all. If I didn't know better I would not even worry about it.
I've ran some like that in 1/8th mile use at around 85mph with no problem but you always run a risk of failure when their old like that.
Another consideration is were they stored off the car (or with the car's weight off of them), or were they bolted to the car, sitting in one spot parked for a long time on the floor? This would be true for any tire ... if parked for a long time, the flat surface can make them take a set and get a flat spot. I am in the tire business and get asked about tire aging a lot. There are no real rules, per se. On my own Comet, which has sat far too long, but up on skates with rounded bottoms, I am confident that the rear tires that are more than 12 years old are going to be OK. Only 10K miles on them and sheltered the whole time. The front tires are another story.... they had a lot more use, and I plan to change them, and they were stored the same way. A couple of burnouts ought to be a good test for the rears. Much better than a high-speed run at first. I will likely take them in to check the balance on them, too. If that has changed a lot, they may have taken a set. Final word ... any tire is risky. I have seen brand-new ones fail. That risk does increase with age and how they are treated.
And it depends on horse power. Lower power, old slick are ok, just get enough burnout to get to clean rubber. The biggest problem will be sidewalls breaking down on higher hp cars. I had problems a few years ago, car would go right every few passes. Changed my 3 year old slicks and cured the problem.
Not a high HP car, went 11.45@116. I looked up the date code on them and they are pretty old, 1\8 mile wouldn't concern me, but my track Milan is a 1\4 miler. The wheels they are on don't have enough back space for my car anyways.
Just keep in mind that old bias plys lose some flexibility with age give less margin to failure points than a similarly aged steel belted design. I'd run em.. but keep an eagle eye on them and work your way up the speed ladder for sure. I've run older tires than that which were bagged up in a basement but I was always white knuckled nervous once I got up to and passed the 100 mph mark. Also remember that IF you blow a tire at those speeds.. neutral throttle can save your life. The guys that abruptly back all the way out of the gas and suddenly force the rear end to compression brake an already unsettled suspension are the ones that usually go for the scariest rides. Or if it's a clutch?.. quickly push it and steer for a quick second or two before you really start using the brakes. IOW, neutral throttle and steer till it's predictable.. then worry about stopping.
