New Dunlop Z2 Star Spec

[Dave-ROR]

Originally Posted by Kamran

New to FRS and ran into this thread. My experience with Z1's weren't so good as you can see from the pix (from trackdys in Pacific Northwest).

Z1's may be ok for autoX since you don't get them finger burning hot or for too long a time (4 or 5 runs, at 60 seconds per run). Doing a couple of full days of trackdays may be different.

These were not shaved, not that you should have to, in order to void serious chuncking. Problem solved with Nitto NT1's.

Just to clarify, this happened running my 3200# Audi Quattro, and not my FRS.

Curious to see reports on trackday tires FRS drivers using...

That's pretty crazy. We run them for 24 hour endurance races and have never had that issue! Literally probably 100 star specs have been on and off the race car by now and not one chunked like that. We do have a lot less weight than your Audi and we are running a bit of camber plus adjusting pressures to get even heat across the tires (as much as possible anyways).

Anyone know the treadwear? I'm hoping the new tires are chumpcar legal otherwise I need to buy a shitload of Z1s....

[Jedi1]

Grab the Z1's anyway. Should be a good sale on them as soon as the Z2 hits the street!

[ayau]

Originally Posted by Dave-ROR

That's pretty crazy. We run them for 24 hour endurance races and have never had that issue! Literally probably 100 star specs have been on and off the race car by now and not one chunked like that. We do have a lot less weight than your Audi and we are running a bit of camber plus adjusting pressures to get even heat across the tires (as much as possible anyways).

Anyone know the treadwear? I'm hoping the new tires are chumpcar legal otherwise I need to buy a shitload of Z1s....

what do you mean by chumpcar legal?

[Kamran]

Originally Posted by Dave-ROR

That's pretty crazy. We run them for 24 hour endurance races and have never had that issue! Literally probably 100 star specs have been on and off the race car by now and not one chunked like that. We do have a lot less weight than your Audi and we are running a bit of camber plus adjusting pressures to get even heat across the tires (as much as possible anyways).

Anyone know the treadwear? I'm hoping the new tires are chumpcar legal otherwise I need to buy a shitload of Z1s....

I check pressure before and after each time I go out, as well as checking the sidewall scuff markers. So pretty well monitored. With Chumpcars, it is about steady speed, not so much hard braking/cornering its about total number of laps, and you are most likely 1,000 pound or more lighter. But if you go out each session as agressively as the car can handle, hard on brakes, etc my tires didn't do as well as others.


I see other much heavier cars with stock OEM setups and non high performance tires putting down twice as much Hp as mine without this issue.


I am using my left over z1's for streets only.

[Kido1986]

the Z1s are all gone in decent sizes and no Z2s yet. I really want to try these tires but I need tires soon for the 2013 season. Everytime I call Dunlop, they put the blame on Tire Rack. I hope one of them gets their act together. I really want to try these tires and if I can't get them now, it will be another year

[jeebus]

Originally Posted by Kamran

New to FRS and ran into this thread. My experience with Z1's weren't so good as you can see from the pix (from trackdys in Pacific Northwest).

Z1's may be ok for autoX since you don't get them finger burning hot or for too long a time (4 or 5 runs, at 60 seconds per run). Doing a couple of full days of trackdays may be different.

These were not shaved, not that you should have to, in order to void serious chuncking. Problem solved with Nitto NT1's.

Just to clarify, this happened running my 3200# Audi Quattro, and not my FRS.

Curious to see reports on trackday tires FRS drivers using...

My stock Michelins look like that after a few AutoX runs.

[ayau]

Originally Posted by Kido1986

the Z1s are all gone in decent sizes and no Z2s yet. I really want to try these tires but I need tires soon for the 2013 season. Everytime I call Dunlop, they put the blame on Tire Rack. I hope one of them gets their act together. I really want to try these tires and if I can't get them now, it will be another year

i called tire rack about a week ago and they said they expect them in feb 2013.

[Dezoris]

Originally Posted by Dave-ROR

That's pretty crazy. We run them for 24 hour endurance races and have never had that issue! Literally probably 100 star specs have been on and off the race car by now and not one chunked like that. We do have a lot less weight than your Audi and we are running a bit of camber plus adjusting pressures to get even heat across the tires (as much as possible anyways).

Anyone know the treadwear? I'm hoping the new tires are chumpcar legal otherwise I need to buy a shitload of Z1s....

Yes thats an absolute extreme case, and clearly there was an alignment and pressure/temp issue there to have those tire disintegrate like that. Been through 5 sets now, never have seen anything remotely close to that. You ever pyrometer those tires in and out?

[Dave-ROR]

Originally Posted by ayau

what do you mean by chumpcar legal?

Treadwear has to be 190 or higher, which eliminates most of the extreme performance tires. The Z1 is/was the hot tire for ChumpCar, I'd say 60% plus of the teams run them.

[Dave-ROR]

Originally Posted by Kamran

I check pressure before and after each time I go out, as well as checking the sidewall scuff markers. So pretty well monitored. With Chumpcars, it is about steady speed, not so much hard braking/cornering its about total number of laps, and you are most likely 1,000 pound or more lighter. But if you go out each session as agressively as the car can handle, hard on brakes, etc my tires didn't do as well as others.


I see other much heavier cars with stock OEM setups and non high performance tires putting down twice as much Hp as mine without this issue.


I am using my left over z1's for streets only.

I understand that, but in this region you have pro teams so you have to be doing 9/10ths or better the entire time to have a chance of winning. We are running about 2,350 without driver.. on 205/50s up front and 195/55 in back.

[Hanakuso]

Originally Posted by Dave-ROR

Treadwear has to be 190 or higher, which eliminates most of the extreme performance tires. The Z1 is/was the hot tire for ChumpCar, I'd say 60% plus of the teams run them.

I believe treadwear is still 200

[Kamran]

Originally Posted by Dave-ROR

I understand that, but in this region you have pro teams so you have to be doing 9/10ths or better the entire time to have a chance of winning. We are running about 2,350 without driver.. on 205/50s up front and 195/55 in back.

Love it! Awesome...


$500 limit on the vehicle with $500,000 semi truck team backups! Yes, I'm familiar with that too!


Raced a GTI in the series. Competitive on the track, and yet very supportive off the track all at the same time! One of our competitors gave us a transmission when we blew up ours!


It looks like Dunlop is reducing the block shear effect with less thread with Z2's. hopefully they have addressed the issue, as they did with their motorcycle race tires. I love their UK made NTec motorcycle tires. The ones with the chunking problem in the link above were, I believe, the GPA NTec which were US made.

[ayau]

You can now order these on TireRack's website.

http://www.tirerack.com/tires/tires....odClar=Limited

[Kido1986]

Seriously NOW?! I just bought a set of RS3s and picking them up tomorrow morning.