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YOUR RESEARCHSumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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Replace a bit scary)
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Never had an issue, even when a bit to worn (Except last rain storm when B4 fronts were replaced - a bit scary)
Sumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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Leading evidence: 'Replace a bit scary)' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace a bit scary)' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Sumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Run set of the kooks
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I've also ran a set of the Kooks on my Box and the main difference between them and the Sumi's is the sidewall which is softer in the Kooks and required a few more pounds of air pressure to keep from rolling over in spirited driving.
Sumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Use z iii's and they were good tires
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I've only used Z III's and they were good tires that gave me about 12K mi.
Sumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Run htrz iii's
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Suggestion
Been running HTRZ III's on the box for 8 years now.
Sumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Run set of the kooks
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Performed · outcome unconfirmed
I've also ran a set of the Kooks on my Box and the main difference between them and the Sumi's is the sidewall which is softer in the Kooks and required a few more pounds of air pressure to keep from rolling over in spirited driving.
Sumitomo HTR Z II or III - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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Generation: 20261026T112012Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
About to purchase first set of new tires and based on forum recommendations have chosen the Sumitomos. Trouble is which ones, HTR Z II or HTR Z III? Both have similar specs and similar prices.
Driving will be street only. Florida location so cold weather performance not really an issue. 2000 Boxster S with 18 inch wheels. Recommendation? Thanks.
I've only used Z III's and they were good tires that gave me about 12K mi. on the rears and double that on the fronts. They're fairly comfortable without a lot of noise and handle well. Had a pair on the rears before I won a set of Michelins and since having those I won't buy anything else.
I can't remember why I didn't go with Z II's, it was something I read about handling not being as good as the III's but can't verify that.
I would never ever ever ever use HTR Z II's again. Not a terrible tyre when new, but they were rubbish after twelve months of daily use on a sports sedan. Downright dangerous.
Edit: my recommendation is to use Michelin PS2's. PS3's if you need more life from the rears. Or try Continental.
My Sumi III's flat spotted and were noisy within a year. I moved to Hankook Ventus V12's because they're a lot like the Michelin PS2's but don't wear out as fast...
and they're half the price of Michelins and about the same price as the Sumi's.
Check them out.
Been running HTRZ III's on the box for 8 years now. No complaints. They're great in the dry, and I don't run in the wet or snow. Tread lasts nicely. I do have a bit of flat spotting after a week in the garage, but it rounds out nicely within five miles.
HTR ZIII is a great low cost tire.
They will flat spot overnight, like schnellman said, they are fine in a few miles.
The Hankook V12 is a good tuire as well, but a few more $$ than the ZIII without any advantage IMHO
PS2's are over rated and the PSS is a better tire
If I had not gotten a free set of PSS, I would have put the Sumi ZIII back on for my DD tires, no question in my mind
Bought car with them on
I put 25k miles on them, 4 season driving
With good tread, never had any issues in the rain. That includes very spirited driving the Blue Ridge Pwy in an all day rain storm
Replaced rears last year, fronts this year. Probably drove them a bit to many miles
Never had an issue, even when a bit to worn (Except last rain storm when B4 fronts were replaced - a bit scary)
I've also ran a set of the Kooks on my Box and the main difference between them and the Sumi's is the sidewall which is softer in the Kooks and required a few more pounds of air pressure to keep from rolling over in spirited driving. Good tires though for the price but not near as good as PSS for ride comfort and noise.
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