Sumitomo HTR ZIII, any good?
08-25-2008, 05:17 PM
#166
Intermediate
Basic Tire 101 - do not mix and match brands or types from front to rear or side to side on performance cars.
As to whether the HTR ZIII is actually the 'Holy Grail' of performance tires - great traction+low noise+high treadlife+low cost - the question is infinitely debatable. That tire may never exist, and probably can never exist (though we have all tried to find it, wasting money on Kumhos, Fuzions, and other tires that seemed promising, but got slick and noisy very quickly).
The feedback in the 9 months since this post began, both here and on TR and other sites, certainly shows that this tire is a serious consideration for any performance car. Additionally, any comparisons that use previous Sumitomo experience are clearly irrelevant, as this tire represents both a new generation of high performance asymmetric, and the infusion of Dunlop-knowledge to the Sumitomo line.
Buy them or not, but they are clearly a strong choice, particularly when compared to much higher priced options.
As to whether the HTR ZIII is actually the 'Holy Grail' of performance tires - great traction+low noise+high treadlife+low cost - the question is infinitely debatable. That tire may never exist, and probably can never exist (though we have all tried to find it, wasting money on Kumhos, Fuzions, and other tires that seemed promising, but got slick and noisy very quickly).
The feedback in the 9 months since this post began, both here and on TR and other sites, certainly shows that this tire is a serious consideration for any performance car. Additionally, any comparisons that use previous Sumitomo experience are clearly irrelevant, as this tire represents both a new generation of high performance asymmetric, and the infusion of Dunlop-knowledge to the Sumitomo line.
Buy them or not, but they are clearly a strong choice, particularly when compared to much higher priced options.
08-25-2008, 06:20 PM
#167
Addict
Rennlist Member
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thx
08-25-2008, 07:23 PM
#168
Well... different tire tread patterns can cause slight handling differences. For example, some tires tend to 'tramline,' following pavement undulations, wear channels, and seams more than other tires. The Sumitomo HTR ZIII in my experience tends to do this more than the RE750s they replaced. In this example, you could wind up with the front of the car following a seam one way, while the rear of the car might react differently. This could really upset handling, particularly at high speed and/or on the track.
Tires also wear at different rates. Remember that treadwear ratings are only relative between the tires of a specific manufacturer and are not particularly accurate between different manufacturers.
As the Tire Rack points out:
So.. tires have different wear rates which is directly related to the relative stiffness or softness of the rubber compounds used in construction. If your rear tires are gripping at a different adhesion level than the fronts or vice-versa, your handling could be significantly compromised.
This problem usually comes down to cost. For example, your rears are gone and are no longer available in the same tire as the fronts - or you find a much cheaper alternative (like the Sumitomo!). My answer - bite the bullet and replace all four. If you are driving your Porsche the way you should, any other solution is wrong.
Tires also wear at different rates. Remember that treadwear ratings are only relative between the tires of a specific manufacturer and are not particularly accurate between different manufacturers.
As the Tire Rack points out:
Unfortunately, the rating that is of the most interest to consumers is the one that appears to be the least consistent. While the Treadwear Grade was originally intended to be assigned purely scientifically, it has also become a marketing tool used by manufacturers to help position and promote their tires.
This problem usually comes down to cost. For example, your rears are gone and are no longer available in the same tire as the fronts - or you find a much cheaper alternative (like the Sumitomo!). My answer - bite the bullet and replace all four. If you are driving your Porsche the way you should, any other solution is wrong.
09-20-2008, 01:29 AM
#169
Instructor
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Jumped on the bandwagon
I just go these tires, and so far I am very pleased with everything about them. The car actually feels much better planted than with my previous Pirellis Pzeros Rossos.
The Pirellis tend to follow every ondulation and grading on the road. They also had a lot of sidewall flex for my taste. Tire wear with the Pirellis was also an issue as I could only get about 5K-6K miles on a set of rears. So when the time came to change all 4 tires, I decided to give these a try.
I'll update this thread once I have some more miles on them, but so far so good...
The Pirellis tend to follow every ondulation and grading on the road. They also had a lot of sidewall flex for my taste. Tire wear with the Pirellis was also an issue as I could only get about 5K-6K miles on a set of rears. So when the time came to change all 4 tires, I decided to give these a try.
I'll update this thread once I have some more miles on them, but so far so good...
).
09-29-2008, 12:27 PM
#170
Rennlist Member
I posted this on the 964 forum HERE
I had the HTR ZIII's (205/50/17 & 255/40/17) put on a few weeks ago and finally got to put about 150 miles on them this last weekend. I replaced a well worn set of P-Zero's and that is what Im comparing them to. My P-Zero's lasted 22k miles and wore evenly so Im not very hard on tires. I could have gone another 2k-5k miles but replacement was required due to melting and cording the P-Zero's during an AutoX on a rough surface course.
The HTR ZIII's are much quieter. I noticed that all tramlining is gone and the car tracks straight on our crappy Calif freeways. The P-Zero's had terrible tramlining. On some twisty mountain roads I felt the tires were very good with smooth and predictable steering response, although they felt less crisp on hard cornering. Having a C4 with the usual understeer I felt there was less understeer on hard cornering. Since I dont know when these tires will break free (and they are very new) I did not push them too hard. No noise during cornering (neither did the P-Zero's) and I did not see any rollover onto the sidewalls upon inspection.
The HTR ZIII's feel smooth and comfortable but thats mostly due to having new tires.
For the price I like these tires very much (HTR ZIII $430 vs P-Zero's $1200). I plan on getting a second set of rims/tires geared for AutoX so the HTR ZIII's will never see AutoX. I will post an update once I get more miles on the tires.
I had the HTR ZIII's (205/50/17 & 255/40/17) put on a few weeks ago and finally got to put about 150 miles on them this last weekend. I replaced a well worn set of P-Zero's and that is what Im comparing them to. My P-Zero's lasted 22k miles and wore evenly so Im not very hard on tires. I could have gone another 2k-5k miles but replacement was required due to melting and cording the P-Zero's during an AutoX on a rough surface course.
The HTR ZIII's are much quieter. I noticed that all tramlining is gone and the car tracks straight on our crappy Calif freeways. The P-Zero's had terrible tramlining. On some twisty mountain roads I felt the tires were very good with smooth and predictable steering response, although they felt less crisp on hard cornering. Having a C4 with the usual understeer I felt there was less understeer on hard cornering. Since I dont know when these tires will break free (and they are very new) I did not push them too hard. No noise during cornering (neither did the P-Zero's) and I did not see any rollover onto the sidewalls upon inspection.
The HTR ZIII's feel smooth and comfortable but thats mostly due to having new tires.
For the price I like these tires very much (HTR ZIII $430 vs P-Zero's $1200). I plan on getting a second set of rims/tires geared for AutoX so the HTR ZIII's will never see AutoX. I will post an update once I get more miles on the tires.
10-03-2008, 10:34 AM
#171
Three Wheelin'
I just picked up a set of 996 hollow's that have new Bridgestone Potenza S02a's. The S02a's are much louder that the HTR ZIII's that came with my car. When it comes time to get some new rubber I will go back to HTR ZIII's.
-dto
-dto
10-09-2008, 02:03 AM
#173
Alright, just got back from a DE event this past weekend. I was running on a set of Pirelli P-zeros and I kept them on for the first day for comparison. Then swapped them with the Sumis. From what I understand, street tires get better in performance as they are shaved down from wear, i.e. they get better grip over time. The Pirellis were two years old however.
I felt like the HTR ZIIIs had better response overall... very good turn-in. Better grip for a brand new set of tires. I was expecting to post slower times due to the uncertainties of a new tire but with every lap I was going faster and faster. I really liked the feel of these tires. Obviously a more accurate comparison would be with new sets of both tires. But for the price difference, you can't beat the HTR III. And ditto on less road noise and less road surface tracking.
I felt like the HTR ZIIIs had better response overall... very good turn-in. Better grip for a brand new set of tires. I was expecting to post slower times due to the uncertainties of a new tire but with every lap I was going faster and faster. I really liked the feel of these tires. Obviously a more accurate comparison would be with new sets of both tires. But for the price difference, you can't beat the HTR III. And ditto on less road noise and less road surface tracking.
10-09-2008, 09:07 AM
#174
So, 10 months and 12 pages of posts - 90% positive. Is it possible that the HTRZ III is the holy grail of performance tires - very inexpensive, highly responsive, and relatively quiet?
Seems like the question that remains is wear... does all this goodness go away abruptly at 10-12k (like the old Kumho Ecsta), or can you get reasonable use from a set? Anything over 20k on a Porsche is cake, less on some models' rears. So if the HTRZ III can keep it together for 20k miles, it really is a winner.
I have 9k on mine, with no noticeable wear or degradation in feel or noise. Anyone gone higher yet?
Seems like the question that remains is wear... does all this goodness go away abruptly at 10-12k (like the old Kumho Ecsta), or can you get reasonable use from a set? Anything over 20k on a Porsche is cake, less on some models' rears. So if the HTRZ III can keep it together for 20k miles, it really is a winner.
I have 9k on mine, with no noticeable wear or degradation in feel or noise. Anyone gone higher yet?
10-09-2008, 09:47 AM
#176
Race Car
I have had mine for 4 months now and about 2K aggressive driven miles. The thread still looks like a brand new tires.
I LOVE these tires. Night and day from the overated and overpriced Pirelli's PZeros.
I LOVE these tires. Night and day from the overated and overpriced Pirelli's PZeros.
12-11-2008, 11:54 PM
#178
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Just put a set on this pm. 225 & 285, on the OEM hollow spokes. Drove all of five miles. Relevance of this post? A friendly reminder that brand new performance tires and temperatures near freezing result in more excitement than I was expecting!
12-11-2008, 11:57 PM
#179
Burning Brakes
Seems like the question that remains is wear... does all this goodness go away abruptly at 10-12k (like the old Kumho Ecsta), or can you get reasonable use from a set? Anything over 20k on a Porsche is cake, less on some models' rears. So if the HTRZ III can keep it together for 20k miles, it really is a winner.
12-12-2008, 12:36 AM
#180
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I bought a set of these tires about a month ago because of all the good reviews and this is my first Porsche. I figured if you guys are debating and putting them in the same league as PS2's at twice the price, a newbie like me will never know the difference. I spent all the money I "saved" on a polisher, HID headlights, car cover, etc.........