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View Full Version : Tire choices after 7 events


Dave Barker
08-18-2015, 12:00 AM
Most of us made tire decisions at the beginning of the season. After a number of events, how happy are you with yours? Lots of other forums discuss different tires but some are for Autocross and some are for longer race sessions. Time-Attack is kind of between these 2 extremes. Do you find your choice of tire consistent during the day? Is your first lap your fastest or your last? Are you faster in the morning or afternoon sessions? Are they heat cycling out or just as good now as when you bought them?

Personally I am on Michelin Pilot Super Sports. 300 UTQG rating, reasonable price from Costco but unfortunately it shows. Consistent and great in the wet with good wear but not overly tolerant of heat. Overall grip less than Rivals or RS3s on my car. My guess is they would make a good chump car tire. Not sure if they are heat cycling out yet.

Gwoody27
08-18-2015, 08:04 AM
I am on Dunlop ZIi Star Spec that were new at the start of the seaso. Grip is very good, consistent and fastest lap is usually thelast but they are good from the beginning, I am the one needing time to warm up.
Wear has been very good also but there is evidence of graining. It doesn't seem to affect performance very much.
I have tried Rivals, RS3s and Yoks over the years and these are the best yet. (255/40/17)

Carguy
08-18-2015, 10:25 AM
I'm on the same tire as Gary - Dunlop ZII Starspec 245/40-17 (2nd gen). Good grip in cooler conditions and wear is on par with other street tires like the RS-3 (2nd gen) and Rivals (1st gen). For best tire performance it's a toss-up between the Dunlops and RS-3s in the 200 TW category. In the future I'll be running R-compounds. I am simply tired of street tires that become greasy when it gets hot.

Greg Campbell
08-18-2015, 12:01 PM
My initial impressions of the AD08R (255/35/18 front and 295/30/19 rear) were quite glowing. And while my perspective on the tire has moderated a bit with more experience my opinion is still positive. Although they are expensive (probably the most expensive street tire size for size) I am actually very surprised that the 08R isn't more common. They are generally vice free, come in a variety of sizes, and have contingency available.

Anywho, additional thoughts:

Extracting performance
While the Yok is relatively easy to drive with good communication about grip and slip and does not punish you for mistakes, to get the absolute best from the tire requires a very precise style. The difference between 'the best the tire can give' and 'pretty fast but just ok' is significant so on balance the tire ends up being deceptively demanding.

Wear and consistency
After 6 events and two test and tunes, the performance of the tire is beginning to noticeably drop off. Front tires are at the wear bars and the rears are not far behind. I have flipped the tires to even out the small amount of shoulder wear that was developing but I do not think that was necessary.

-3.0 degrees of camber was a good starting point, but for best performance I think I should have gone with -3.5 in the front. Rear camber a -2.0 is pretty much perfect.

The Yoks continue to be very consistent lap over lap and run over run. Long practice runs on a hot day (Calabogie and SMP) are limited to 3-5 fast laps before grip falls off to the point that you should take a cool down or drive through the pits. While overall performance is starting to drop off, the reduction is slow so there's no big 'fall of the cliff' that some experienced with the original Rivals.

Overall Performance
When new, the overall speed of the 08R is a match for an RS3. RS3s generate slightly more lateral grip but 08Rs are better under braking and turning into the corner. On the same car, the Yok will probably last longer in terms of treadwear and grip throughout its life. The difference between the two is not a night and day difference for the stopwatch and what tire is better for you is going to depend on your personal preferences and car. A heavier, camber challenged car driven by a less experienced driver is probably going to be faster on an 08R as that tire's shoulder will hold up better and performance will be more stable lap to lap allowing you to have multiple 'kicks at the can'. A lighter, good camber curve car, with a more experienced driver might be happier on the RS3, if the driver is ok with slightly less communicative tire that tends to take a moment to settle in the corner.

IWannaGoFast
08-18-2015, 12:38 PM
Iím also on the Dunlop ZII SS and Iím fairly happy with the tires, good grip, communicate well, and break away gradually. Tire wear has been a bit of an issue though, as I found I could make RS-3s last a full season with many lapping days in between, but last year the tires were corded after GBR and this year with only our 6 events on them and a couple of lapping days, SMP used up most of what rubber was left

10gt61
08-18-2015, 01:00 PM
Before my season ended this year I did have a couple of track days at MIR. I used my 2 year old ZII's the first day (JRP) and last year's ZII's the second day (Mustangs at Mosport).
I was very impressed with how they maintained grip and the wear is outstanding. I was actually faster than last year and did a PB lap on the 2nd day. I don't even know if I would have needed new tires this year!
For reference, my previous tires were NT05's and I've never used R-Comps.

Grant Galloway
08-18-2015, 04:04 PM
Although I have only done the one OTA event, I can tell you that I have run 9 track days this year. I started with the Hankook RS-3's from last year and they are still holding up well!

I bought the RE71R's that Corey and myself ran at the TMP event, The front left was so bad I had to replace it. I then ran the new tire up at Grand Bend with a new setup -3.5 camber and heavy rear sway bar and after just two sessions the brand new tire showed signs of wear.

Perhaps it's the FWD car..

Although they are a fast tire, I will switch back to the RS3 next year! As I plan to run the entire series and although I could afford new tires every event, I will not be doing that! I do have a special tire mounted up for GT2 for the Grand Bend event on the 29th and 30th I will be testing up there this Thursday to see how fast they can go!

Gwoody27
08-18-2015, 05:53 PM
I wanted to add a comment about R comps. I was luck to run 2 days at the new Corvette track in Kentucky. Both days had similar weather and I started with BFG R1S tires that were 2 yrs old but had only 1 heat cycle. Day 2 I used my new ZII SS tires. The R comps were 4 sec faster for a 130 sec lap, not as much as I expected.

I again used the R1s at MIR for the school day and the ZIIs for competition. This time I felt more confident in the Dunlops and actually went .6 sec faster on the 2nd day. Maybe I was just getting better, or the weather was better?

Did the same a CMP, R comps Sat, Streets Sunday. Went 1.1 sec faster on Sunday. I now believe that I just don't know how to the the best out of the R-comps. Both tires still have lots of tread left and the Rs have not cycled out.

nowcritical
08-23-2015, 11:34 PM
I'm happy with my Sport Cup 2s. They are the most capable street tire that I have ever driven on at the track . If I used them for OTA only events I think a set would last the season. Drive them to the track use and drive home, swap to a more friendly or affordable compound for day to day street use. They are fine in the rain at highway speeds.

The tire has lots of grip seems to come up to temp fairly quickly and is consistent. When you overheat the tire it does feel greasy and does loose grip. Keep an eye on tire temps and pressures.

Considering the design goals of the tire and the likely audience I think these are fair ware and care items. They do have a very stiff side wall so a proper shop is a must when mounting and discounting the tire. I had tire get ruined as a result of a rookie trying to do the installation. Not to mention that a rim was damaged in the process.

Dave Barker
09-08-2015, 09:21 AM
Any new thoughts after 9 events? I noticed that some drivers changed brands near the end of the season. Heat cycling an issue? Would you buy again ?

New tires for the shoot out?

Greg Campbell
09-08-2015, 10:35 AM
I am going to have to modify my reivew above as the AD08Rs have very much hit a performance 'wall' and have dropped off significantly.

As Mike pointed out in the data files for the first couple of events the Yoks generated up to 1.4g at the DDT and MIR events. However at the last two locations (SMP and GBR) g was down to 1.1. While there is certainly a difference in track surface and ambient temperature at play my lap times have fallen off the overall PAX pace.

I managed to get 5 competitive events out of them (T&T, DDT Lapping, DDT#1 and #2, and MIR) before they dropped off. The heat of Bogie mortally wounded them and SMP was the death knell.

I don't think that I've been particularly hard on the tires, but I think I took all the available grip early in their life which caused them to drop off.

Dave Barker
09-20-2015, 10:33 PM
Well, the PSS tires seem to overheat but not heat cycle out particularly. Greg started out miles ahead of me at the beginning of the year but almost within reach by the end.

Still think they would make a good Chump Car tire.

wparsons
09-21-2015, 08:40 AM
Greg, how did you find the AD08R's on their first couple sessions? I finally got mine mounted, they only had about ~400km of street driving on them before yesterday, but they didn't seem to have anywhere near the grip the RS3's that came off the car had, and they had about a dozen days on them, plus a full summer of street driving. It was both braking and lateral grip as well.

I only put two 15 minute sessions in, but they don't even look like they have track time on them yet.

Greg Campbell
09-21-2015, 02:17 PM
Greg, how did you find the AD08R's on their first couple sessions? I finally got mine mounted, they only had about ~400km of street driving on them before yesterday, but they didn't seem to have anywhere near the grip the RS3's that came off the car had, and they had about a dozen days on them, plus a full summer of street driving. It was both braking and lateral grip as well.

I only put two 15 minute sessions in, but they don't even look like they have track time on them yet.

In my experience AD08Rs are fastest their first day, and then very slightly drop off after that hitting their 'wall' somewhere around a half a dozen hard days (call it 30 heat cycles/track sessions). The Yoks don't need any kind of 'coming in' period before giving up peak grip. Just a session or two to get the mold release off (which you can never fully do on the street).

While I believe that the overall level of grip between the 08R and the RS3 is comparable the tires provide their grip in different ways. The 08R rewards a very precise drive with no slip while the RS3 tends to do better with a little sliding here and there. That means that a fast lap in the 08R is neat and tidy, which may not register well with ye old Butt Dyno compared to a slightly more 'spectacular' lap on the RS3.

Pressures for the 08R tended to be 2-4 psi up on the RS3. And yes, they do wear like iron. The set I have on my car is completely heat cycled out, however the rears are not even at the wear bars. YMMV.

Will, I would say that the 400km of street driving didn't do anything and it was only your two track sessions that event begun to get the mold release off. I think you'll find that the next track session you have will be the best the tire has to give.

kmorris
09-21-2015, 02:49 PM
My R888s are still fresh as a daisy.:D

I guess 350# of vertical load on the tire is well within their design capability.

wparsons
09-22-2015, 04:52 PM
While I believe that the overall level of grip between the 08R and the RS3 is comparable the tires provide their grip in different ways. The 08R rewards a very precise drive with no slip while the RS3 tends to do better with a little sliding here and there. That means that a fast lap in the 08R is neat and tidy, which may not register well with ye old Butt Dyno compared to a slightly more 'spectacular' lap on the RS3.

Pressures for the 08R tended to be 2-4 psi up on the RS3. And yes, they do wear like iron. The set I have on my car is completely heat cycled out, however the rears are not even at the wear bars. YMMV.

Will, I would say that the 400km of street driving didn't do anything and it was only your two track sessions that event begun to get the mold release off. I think you'll find that the next track session you have will be the best the tire has to give.

I was hoping you would say that. They did seem to get better at the tail end of the last session.

I was expecting them to be more like the ZII's I had before the RS3's in driving style, given the stiffer sidewall (and they are). I definitely like the feel better than the RS3's, especially with a camber challenged front end (yay mac struts!)

Greg Campbell
09-22-2015, 05:10 PM
I'm certain that the next time you hit the track you'll be pleasant surprised at the grip. Two short sessions (I'm assuming at the super low grip DDT) on a light car will barely clean them up.

They are a good tire. My issues are due to me specific factors (no heat cycling, slightly undersized, taking all the available grip all sessions, and drive by like a lunatic).

wparsons
09-22-2015, 05:59 PM
I'm certain that the next time you hit the track you'll be pleasant surprised at the grip. Two short sessions (I'm assuming at the super low grip DDT) on a light car will barely clean them up.

They are a good tire. My issues are due to me specific factors (no heat cycling, slightly undersized, taking all the available grip all sessions, and drive by like a lunatic).

Yep, it was the DDT, and short sessions (~10 minutes)... I was trying to do too many different things so I wasn't taking full sessions.