When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This is my time using the Hankook Z214 DOT racing tire, which is the new PCA spec cayman tire for this season. Corded the inside edges of both rear tires on the 15th HC after just running a bunch of PB laps of Mosport on the 13th and 14th heat cycles. 2006 Cayman S with complete spec suspension + 3 way dampers.
Hankook recommends 32psi hot, but everyone actually running these tires says run them like R7's - 35 to 38psi hot. I definitely ran them closer to the 32lbs for the first 12 HC, then increased to 35-36psi hot for these last 3 HC yesterday when they corded.
Other than the inside edges the tires wore well, and the fronts a still good too. Went through many many sets of Trofeo R before these Hankooks on the same alignment, perfect tire wear on them. So what do you think? Air pressure too low for these tires? Bad rear toe setting? I have an appointment on the alignment rack for this friday but would like some armchair opinions in the meantime.
The tire's construction looks inadequate for the load you are putting on them. This wear pattern is very common in that scenario. Your alignment is super conservative so realigning it won't help.
The other possibility is severe inside wheel spin due to lack of or malfunctioning LSD.
When I tried Z- 214 I had the same results but only on the LR running at WGI. I had just had a shop install MCS 2-Way shocks and took it back to them. After an-alignment check and adjustment I had no issues other than finding a replacement tire.
The tire's construction looks inadequate for the load you are putting on them. This wear pattern is very common in that scenario. Your alignment is super conservative so realigning it won't help.
The other possibility is severe inside wheel spin due to lack of or malfunctioning LSD.
Chris Cervelli
Cervelli Technical Service
This are the spec PCA racing tire for Spec Cayman club racing. And my car is 2750 lbs wet, without me in it. So I don't think it's a case of not being up for the job. Also have a Guard diff in the car so that's not likely it either. I was thinking that maybe I am putting too much slip angle in them, and I am pulling the inside rear wheel around corners? Very odd, as the Trofeo's don't have any uneven wear on the inside edges at all.
I'm quite interested in what we find on the alignment rack Friday and whether something has gone out of spec. I have every nut and bolt in the suspension paint marked, and I check everything religiously including between sessions and nothing looks to be out of place. I have a fresh set of Z214s to mount up, but definitely hoping to have an 'ahhh-ha that's the problem right there' revelation before then.
When I tried Z- 214 I had the same results but only on the LR running at WGI. I had just had a shop install MCS 2-Way shocks and took it back to them. After an-alignment check and adjustment I had no issues other than finding a replacement tire.
Interesting, this is also the alignment from when I had 3-ways installed. Albeit I've gone through a set of trofeos since the installation without issue, but it hasn't been rechecked since the new dampers were put in.
I've gone through a bunch of sets of the same tires on my Cayman and I can offer some suggestions.
First of all, 15 HC's is a lot. Depending on the track, the length of the sessions, and how hard you were driving, it's very possible the Hankooks simply reached the end of their life. I've gotten up to 20 sessions on those tires. But they are no longer competitive after 7 or 8.
My rear suspension setup is similar to yours. I frequently wear out the inside rears before anything else shows excessive wear. On my last two sets of Hankooks I delaminated the inside rears and the steel belts were showing.
I honestly don't think you have anything to worry about. I wouldn't change a thing if I were you. But if you want to run competitive lap times you're going to have to swap tires for fresh ones sooner.
This are the spec PCA racing tire for Spec Cayman club racing. .
How does that guarantee that the tire is suitable?
Your Guard diff is likely good. Was the front sway bar functioning correctly, that is, both end links were hooked up?
The other thing to check is excessive roll understeer. This would happen if you have rear toe links that are adjustable for bump steer and they are set in the wrong position.
After running well over a dozen sets of Z214 C51s on 987s, I can offer some insight. I race but my 987s were not race cars. Street 987 Spyders, actually.
My take? Too much negative camber. I know that sounds like heresy in race cars, but I discovered that Z214s do NOT like a lot of negative camber. I regularly cord both inside and outside shoulders of Hankooks. As a matter of fact, that's when I switch them out. But the problem was that I was cording them (down to steel belts) sometimes in 2 days... after heat cycling too...
I drove fine for years on NT-01, BFGoodrich R1, and Hoosier R6 and R7. When I went to Hankooks, immediate cording issue on not-even-race-car alignment. After much trial and error, I gradually decreased negative camber little by little. Inside cording became MUCH better after I finally got down to -2.2 in front and -2 in rear. I know, not ideal for racing.
This may or may not be applicable to SPC, but that's been my experience in two 987 Spyders at DEs (running lap times not all that different from SPCs). My car was roughly 2850-2900 lb., mostly stock. I ran 33-34 psi hot. Anything lower and it would take a looooong time to reach those pressures, at least for me (I still used TPMS on track then check with real gauges). I don't run Hankooks on my race car but that's mostly due to regs (Hoosier and Toyo).
^^^EDIT: oh yeah, I did get TONS of understeer, but most likely a driver issue. Need to work more on DvM's trail braking down to the apex...
EDIT 2: For anyone interested, I have some sticker C51 probably for sale. 245/35/18 and 275/35/18 bought last year from TR. Probably moving to a GT3 and will be having a garage sale of 987 parts.
Agree with above . 15 heat cycles first of all the tires are shot long before you lost the rubber . You lost your wear indicators on 3/4 of the tire as well . You used up all the rubber definitely got your money worth out of that tire
I ran -2..5 degrees of rear negative camber (-3.0 on front) on my 993, corded the inside rears after about 6 HC. The car had recently been aligned....hmmmm. I knew the alignment was good, all ERP suspension components, MCS suspension, 993 RS bars, Tarrett Drop Links....off came the Z-214 tires and on went either NT-01 or Hoosiers, can't remember.....no more cording problems. This went on for several years until I sold the car.
The price on the Hankooks is tempting with the assumption that they'll wear at least a well as Hoosiers....but because of the poor availability of this tire, I have not since been tempted to get another set. That 6 HC # just won't go away, thanks for reminding my why I don't want Hankooks.
I'm surprised PCA picked Hankooks for a spec tire given their notorious supply issues in the past. In my opinion a longer lasting tire makes more sense of a spec class, even at the expensive of performance, since everyone is running the same tires. We ran the Hankooks on a similarly prepped Cayman S with similar results. They didn't last and neither of us liked the tire much (ran them at Streets of Willow and Willow Springs). We didn't spend much time troubleshooting it, just changed tires since we aren't limited by the rules. If the Hankooks are that sensitive they would be wise to provide PCA with a recommended operating window (pressures, alignment, heat cycling, etc) specific to the Cayman spec cars, otherwise they risk developing a bad reputation among the racers.
Thing about Hankooks is that they can be fantastic under the right circumstances. Much cheaper than Hoosiers, last longer with the right set up, and only 1-2 sec slower (at most) than Hoosiers. At least that's been my experience in 987.
BTW, when I had a friendlier set up and didn't cord them so fast, I'd get way more than 20 HCs. Not as sticky after a while but who cares, it's DE.
This is a great discussion and lots of feedback that isn't really available online - especially for our cars. Good to know this is not uncommon.
I am not racing - I am doing open lapping and DE events. While I am quick with a clear track, more than half of those 15 HC's were typical PCA black run group sessions where they've allowed too many cars on track to really have a good time.
All the research I did showed the Z214's should easily go 20-24 HC's with my mixed use of DE and open lapping. These Z214's had lots of stick left when they corded, 5 minutes before they corded I ran this 1:31.1 lap at Mosport - my personal all time best.
I have another set of Z214 to mount up this weekend after checking the alignment to ensure nothing went out of spec. I am going to run higher pressures targeting 38 hot and see if I get better life out of the 2nd set. If not, I'll be going back to Trofeo R. Same price as the Z214's, and I get 20 to 24 HC's out of them like clockwork (and always HC them out before they cord).
06-19-2019, 06:23 PM
R-comp tire wear - corded inside rears
