Not so much... See my reply above ^^^ (post #30)
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I still don't agree. An RE-71R is about as fast and lasts as long as an R-comp. I'd send every student out there on some shitty all-season tires if I could. That way, they can learn the signs of a car at the limit, and how to drive it and maintain it there, at relatively low speeds. All you're doing when you put a newbie on R-comps is a basically assuring that, when they go off, they go off fast enough to really stack shit up.

 

Pretty pinched looking on those 9's. Definitely want to pair those monsters up with a 10" wheels to maximize there handling and grip performance. Those look wide enough a 10.5" might even work better!

 

The difference in actual cornering speed between a tire capable of 0.9 g and on capable of 1 g is not that much. Lateral g's = V^2/r (velocity squared divided by turn radius), so cornering speed at 1g is only 5% greater than cornering speed at 0.9g, not 10%. 63mph vs. 60 mph. How grip changes with slip angle at the limit is WAY more important than outright grip. And in this category RE71R and NT01 are almost certainly better than "shitty all-seasons".

I've been out with a lot of students over the years, a few that "got it" pretty much right away, some that would clearly *never* "get it", and the vast majority that learned and got better as they went. As far as I'm concerned, *none* of them would have developed driving skills any better on shitty all-seasons.

IMO it is more important for students to be on tires that are consistent and can handle a broad range of temperatures, and that have a goodly amount of sliding grip.

I would rather be out with a student on RE71Rs or NT01s (or R1s or R7s!) than "shitty all-seasons".

 

I suppose. I'm happy I learned to drive, and fully exploit crappy tires. It meant that when I put good rubber on the car, I was able to use 95% of the grip right away because I developed good habits at comparatively low speeds, and on tires that made it readily apparent when they were giving up the ghost. R-comps and the majority of 200TW street tires tend to hide a lot of little mistakes a novice might make because of their ability to grip even when mistakes are made. In order to go fast on something like an all-season, you need to be as smooth as possible and be able to feel the grip leaving in real time, something a student may not be comfortable or able to do right away. To each his own. I've coached plenty of guys in average cars with average tires, and they always seem to end up being faster than the guys that bought R-comps because the internet told them it was a good idea.

 

My last track experience on street tires is quite old (just under 40 years), but at the time street tires were very prone to chunking. We shaved them down to about 4/32-5/32 to minimize that.

Do all-season tires or even high end street tires like the Pilot Super Sport avoid chunking in a 20 minute session on a race track, especially limited to less than 2° negative camber?

 

My student this weekend in a future SpecE30 build was on Kumho Ecsta ASX tires, so a 420 treadwear all season tire. He let me drive it in two sessions, and I drove it like I would drive my SpecE30 on Toyo RRs, and it worked just fine. The tires didn't destroy themselves or chunk. They squealed and communicated the level of grip available to me much more than the Toyo RRs would have. I always tell my students I don't care what tires you showed up with as long as they aren't going to cord and you are going to miss track time you paid for. All tires have a level of grip available, and a good driver is able to get to that limit and extract the maximum performance out of any tire they are given.

 

I did 8 25 minute sessions in the middle of June in South Carolina on Conti DWs, they didnt chunk.

 

I'd say that's the most important feature of a street tire versus an r-comp or r-comp-like-street-tire.

Sadly, I was not the next Lewis Hamilton at my first track day event (nor will I ever be...), but the audible feedback of my tires helped me with hearing the limits of the tires where I was unable to feel them due to a lack of talent.

The much higher grip tires and r-comps don't have anywhere near the audible feedback that street tires due. It's one of the reasons the RE-11 and RE-11a was one of my favorite street tires early on. They had excellent audible feedback to compliment the overall feel of the tire as opposed to something like the RS3 that just felt numb and quiet when approaching the limits by comparison.

 

Good lord what is the measured width of the Trofeos compared to the RE71R?

 

Tire Rack will have all that information. I use it often to compare tires:

RE71R: 255/40R17 8.5-10" 9" 10.2" 8.9"
Trofeo R: 255/40ZR17 8.5-10" 9" 10.2" 9.2"

The difference is .3" in tread width for the common 255/40/17. Note the section width is the same when mounted on a 9" wheel.