Those of you following my reviews of Sumitomo’s recently released summer tire, the HTR ZIII, may be wanting to hear more good things regarding this tire and it’s track-worthiness. Unfortunately, you may be a bit upset with me after I’m finished writing this. I’ll keep it somewhat short as well.
As I write this, the test car, a 99 FRC Corvette, has been sold for a few weeks now but not before I had the chance to flog it one last time. The track of choice? Summit Point’s Main Circuit, a 3-day long venture of fluid boiling, serpentine belt shredding, tire smoking, rotor cracking fun! Add to that pegging off the rev-limiter at 140+ MPH in 4th gear on the front straight. So much fun. You know what would have made it even better? Not having Sumitomo HTR ZIII’s wrapped around my SSR GT2 wheels. Oh my — did I just say that out loud?
So this would have been the what, my third or fourth track day on these tires? And they’ve been heat cycled plenty more than most people would dare. In Sumitomo’s defense, up until this weekend they were great. So what was my issue? My first issue was sidewall flex. After that first day back on track in the scorching hot Virginia heat the sidewalls on my Sumitomo HTR ZIII’s threw in the towel. I’d make a steering input, glance down at my gauge cluster, check my side mirrors, open the visor and wipe the sweat away from my eyes, and finally the car would react. OK, so maybe it wasn’t quite that bad. But Josh, what about your tire pressures? Did you even check. Yes, newb, I checked. They started off at 35psi all around and ended up at around 42psi after about 20 minutes. The wear on the tires were right on the indicators on the sidewall.
The next issue I had was braking distances. Let’s face it, braking performance numbers were never the strong point of these tires. Maybe it was my choice of brake pads, Performance Friction Z-Rated, but I doubt it. The ABS would easily engage in the brake zone with minimal pressure on the middle pedal. Or in any zone for that matter. Sumitomo, regardless of the day’s performance and conditions, the braking characteristics of your summer tires fell below average as far as I’m concerned. They were also quite vocal. Not that vocal’s bad, but I swore I heard them squealing before I even got in the brake zone.
Alright, so I’ve covered the sidewall and the braking performance. What else? Well, that’s probably about it, honestly. To recap on the sidewall, I feel if you’re just tracking your car once or twice, and it’s not a big heavy pig, then you’ll probably be fine. Hell, you might not even notice if you track your car more than I did. But the braking, well, if you’re used to using cheap tires, then it’s probably not much different than what you’re accustom to. If you’re coming from say, Yokohama AD07’s, then you’re gonna be wearing a sadface around the paddock for the entire event, most likely wishing you weren’t such a Joou… err, cheap bastard, when it came to your tire selection.
After my ownership of these tires I’d definitely recommend the Sumitomo HTR ZIII to those on a budget. They’re not bad tires at all. I wouldn’t recommend them for much more track use than a few HPDE1-2 sessions. The Sumitomo HTR ZIII tires may please your wallet, and if your car never sees a track, they’ll probably please you, too.
Ok, this is just a little rant. Around the beltway here in Virginia there are several areas where the good ‘ol VDOT construction has laid down solid lines that go on for maybe one eighth of a mile. It doesn’t matter why they are there. The fact is, they are, and some official deemed it necessary. Day after day I see commuters crossing these lines, making regular lane changes, oblivious to the the new solid markers. Did these people not take a drivers test? Do these people have no idea what they are for or are they truly just ignorant bandwagoners on their way to “Vote for change”? Maybe they’re making a statement. Something about crossing new lines? Oh for fucks sake. I wish I had a massive air horn from a locomotive strapped to my car so that I could lay on to these douchebags just as they start to cross. They’ll probably be startled, wondering what they were doing wrong. And that’s the problem, America, they don’t know. Lack of education.