Saw this link on Nitto and Khumo tire comparison. Thought some people might like it.

http://www.gmhightechperforman...ppin/

 

Looks like the Kumhos overheated really fast where the Nitto's took it. Perhaps on a lighter car the kumhos would end up being better than the nittos. That trans am probably weighs twice as much as most of the cars we are driving. Good article though.

 

unfortunately, until more sizes are available for the NT555R II, it is a non-option for just about anyone on this board.

 

wait, i was under the impression that the 555's were drag radials?

 

Interesting results! To be fair, the V700s timed laps came at the end of the first day, while the Nitto laps came at the end of the second day at which point the drivers had doubled their track time. Even when not on a new track most people seem to turn faster times on day two out of a two day event, so their results are not surprising especially considering that this was their first time around the track. It's very unusual for the harder tire (that squeals in the turns) to be faster than the stickier softer tire, assuming both tires can be optimized in size and temperatures on a given car. As even they mentioned this didn't seem to be the case, with the softer V700 being in the wrong size for the car and probably just overheated way too much. I’m surprised they didn’t start to chunk if that’s the case.

Still I got a kick out of this quote from their introduction "Even having all the cool suspension parts on your car, as one soon finds, has little benefit if you're sliding through a gravel trap at 100 mph because you've got hard-compound street tires!" Yes, indeed it is the tires' lower grip level that just "caused" the car to go off the track. Whatever happened to the concept of just being able to drive within the traction circle (big or small) of a given car? lol

 

The whole comparo is flawed because the V700s are not intended to be driven on the street. He had 500 street miles on them before going to the track!!! Yes, he wanted a dual purpose tire but the V700 (or V710s for that matter) are not that kind of tire. A better comparison would have been the new Falkens.

 

For everybodies information, this article is 3 years old. I do like the Nitto NT-555 RII's, the've been good to me so far and have been daily driven for quite a while in between autocross events. $150 a tire for 275/40-17 size with heat cycling is not a bad deal for an entry level DOT R tire. Plus it's streetable and traction level hasn't gone down noticeably yet 1 track weekend, numerous autocrosses, 2 days of Evolution school, and countless weeks of being daily driven later.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jpl95si &raquo;</TD></TR><TR><TD CLASS="quote">The whole comparo is flawed because the V700s are not intended to be driven on the street. He had 500 street miles on them before going to the track!!! Yes, he wanted a dual purpose tire but the V700 (or V710s for that matter) are not that kind of tire. A better comparison would have been the new Falkens.</TD></TR></TABLE>

That is in part true, but 500 street miles is virtually nothing to affect the performance of an R compound, as they would hardly even get warm compared to track temps if you stuck a pyrometer into them, and heat is what affects those long chain molecules making them convert and get re-organized until grip falls off. I have had to drive that on my Sport Cups in my NSX going to and from a track due to lack of auxiliary tire transport once, and I can assure you there was no effect on grip, as shown by my data logger. Same g's, same lap times.

Anyhow, I always like comparison tests, flawed or not, as there is always more to learn than in reading opinions on a single tire without another one to compare it to. I was once discussing brake pad performance with Andy Lin at Cobalt Friction, and sent him some longitudinal g-charts of different brake pads on same tires including his Spec VR's, same corners, both pads on two different cars (NSX and ITR) to show him that his pads were not stopping the cars any faster or better than some Hawk ones. Initial, middle and end of braking sequence was virtually identical. It was all limited by the tire, not the pad. But it was nice to compare two products, not just my guessing that this pad was better than that pad. All tests are flawed in some respect. I posted tire test done by Will Turner and Don Salama whom you would think know how to drive a tire on the limit, and half the people who posted replies said they thought those tests were flawed, perhaps because they were not reported in an SAE paper but rather in some "lowly" magazine called Super Street that actually accepts tire ads. But I learned a lot.

I say we need more comparative testing, as there is just too little of it going around. Grass-Roots Motorsports did a couple of nice tests on R compounds, one with a guy I met at a suspension design seminar who builds very nice little Spec Miatas (BM I think). I wish they would do more, as I can't afford it. R3S05's, Sport Cups, Avons, Khumos, RA-1's would be nice.

 

Just out of curiosity, were the V700's shaved? It looked like they were, but I didn't see it written anywhere. It may have been, and if so then that's my fault for poor comprehension, but I was just wondering because I think Kumho says the V700's MUST be shaved to 4/32's for dry track use.

Has Nitto offered more then three sizes yet?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr Hammond &raquo;</TD></TR><TR><TD CLASS="quote">Just out of curiosity, were the V700's shaved? It looked like they were, but I didn't see it written anywhere. It may have been, and if so then that's my fault for poor comprehension, but I was just wondering because I think Kumho says the V700's MUST be shaved to 4/32's for dry track use.

Has Nitto offered more then three sizes yet?</TD></TR></TABLE>

Kumho says the Ecsta V700 must be shaved, not the Victoracer (the tire in question in this test).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sean O’Gorman &raquo;</TD></TR><TR><TD CLASS="quote">

Kumho says the Ecsta V700 must be shaved, not the Victoracer (the tire in question in this test).</TD></TR></TABLE>

You sure?

http://www.tirerack.com/tires/...+V700