Here it all is again...
"Billboards" refer to the Sports Car Specials. They are the "B" group at the Krause site Ernie (Excaliber) linked for you. They are rain tires. They barely hunt (less than Hoosiers or Bluestreaks) on the street...unless you're on a grooved freeway (My C6 Vette's Goodyears hunt more than they do). And for the flat spot worry-worts, it goes away in a mile.
They do a good job in the rain and even light snow (I've driven them over Mt. Rose near Tahoe twice and the Carson Pass once in light snow...I'm still alive). Their temp rating is a little lower than a hand cut slick or Bluestreak, which is a good thing (having a tread is only part of the story...you need a tire to operate at lower temps to work). They do a good job on the track as well. They are a bias ply tire...easy to plug if you pick up a nail...at least to get to a service station. After several thousand miles of driving on several sets over the years, I have yet to get a flat (I will tomorrow having written this).
Folks keep trying to come up with excuses for not using them...they still are the best all-round tire for a Cobra running proper 15" wheels.
Several of us just ran the sh!t out of them all day at a hot track at the Bash, and then calmly ran them through the Sierra Nevadas around Tahoe for a 100+ drive the very next day. Some folks drove home on them the next day. And we've done that for four years. What the he!! more do you want for a referral? Any more, just get your own set and try them...or don't!
Bluestreaks are NOT Billboards...arguments start because folks use the wrong terms. They are the "A" group at the Krause site. Bluestreaks have a stickier rating, and though they have a rain tread are no way as good in the rain as the Billboards (their temp rating on the most commonly available compound is higher)...though they are stickier on the track in the dry. I would say they are downright dangerous in the rain.
Avons are being promoted lately...more money, and for me...not quite the look I want. Drag radials seem to work well at the track (even one with curves which they were not designed for). Depends on the look you want.
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