[Vote Quimby]

Originally Posted by LuvMyE92

Looks like you guys have the pressure questions covered pretty well.

I will share an anecdote, if I may, perhaps in the hope of paying it forward.

I was at Road Atlanta many years ago - wanted to get just one more weekend out of my tires.

Just one more.

I lost traction (somewhere, who can remember?) and then lost control and stuffed it into the wall, airbags deployed but fortunately I had a harness bar & five points for both of us, so no permanent injuries.

Never again. Never try to save money on tires.

Oops. Lost track of this thread.

I've been chunking and cording tires at the track for over a decade now. RE050A's were barely good for a weekend on a tuned N54 E90, but they were basically free and in endless supply as OEM take-offs so I just ripped on them until they chunked - at which point I swapped them out immediately. So the first question there "How about now, LOL?" was a joke and I assumed it was clear as such (hence the "LOL"), and the second one "Is this to be expected after 20 heat cycles, each 20 to 25 minutes in duration?" was in earnest, because I'm new to Cups and used to getting more out of PS4S's on my F80. beachBmmr answered both because he consistently knows things about stuff.

Regardless, you're absolutely right to advise caution and I'm probably offside being too cavalier in my humour, given the risk that someone reads the thread too quickly and misinterprets it.

But that said, with respect to your particular anecdote, I'm not aware of tires with low tread that are otherwise sound (i.e. even wear, not ages old) providing less predictable grip (presuming it's dry) or being materially more likely to blow out catastrophically, which is the real fear when you're chunked or corded and have physically exposed the belts. But if I'm wrong here everyone jump in and correct me.

And I'm sorry about your accident. That sucks. Glad you're OK.

[LuvMyE92]

Originally Posted by Vote Quimby

But that said, with respect to your particular anecdote, I'm not aware of tires with low tread that are otherwise sound (i.e. even wear, not ages old) providing less predictable grip (presuming it's dry) or being materially more likely to blow out catastrophically, which is the real fear when you're chunked or corded and have physically exposed the belts. But if I'm wrong here everyone jump in and correct me.

And I'm sorry about your accident. That sucks. Glad you're OK.

Thanks.

Yeah, this was a long time ago (25 years) and I can't remember the name/brand/model/size of the tire except that it was OE for Corvette back in the day. And for those tires, yes, it seems that they had multiple compounds in the tread portion (all tires have multiple compounds in them) so that as they wore, they performed worse.

I don't know if that's as true today. I'm guessing not, as tire technology has come a long way. I also remember a lot of guys at these HPDEs running corded tires - knowing that it was showing cord but saying "I can get one more session out of these" and often, they did make it. Once or twice, they didn't.

[Vote Quimby]

Originally Posted by LuvMyE92

Thanks.

Yeah, this was a long time ago (25 years) and I can't remember the name/brand/model/size of the tire except that it was OE for Corvette back in the day. And for those tires, yes, it seems that they had multiple compounds in the tread portion (all tires have multiple compounds in them) so that as they wore, they performed worse.

I don't know if that's as true today. I'm guessing not, as tire technology has come a long way. I also remember a lot of guys at these HPDEs running corded tires - knowing that it was showing cord but saying "I can get one more session out of these" and often, they did make it. Once or twice, they didn't.

There are definitely multiple compounds baked in these days, but I believe that's more sidewall vs. shoulders vs. centre. And if there is some hard compound at the bottom of the tread to protect the cords it's bound to be a progressive transition or it would just snap like hitting a coolant patch when you wore through to it. Maybe that's how it was back then and that's exactly what you did. Hard to say this far down the road.

Summing up, though: driving on cords is stupid. Even if they don't blow out they're not rubber and have no grip.

[froz3ng80]

I have pzero's what is recommended pressure?