~ KUMHO education needed.....V710/V700/Victoracer....

[Craig 930 RS]

What are the subjective differences between these tires:

Ecsta V710
Ecsta V700
Victoracer V700

I've read the specifications.
I need to know the BTDT on the differences of these 3 to make an informed decision -

TIA,

[juanbenae]

AX'ing Victoracers, air pressure, observations and other musing

there's a story above. search the ax/race area there are a couple kumho track tires threads.

[MuffinMan]

Ecsta V710 - Supposedly Kumho's answer to Hoosiers. I heard drivers arrived at the SCCA national autocross championships this year with new Hoosier autocross tires mounted, and purchased new V710s while there in order to be competetive. I have not run them, but from what I gather you get stick at the cost of life. The life is supposedly ~the same as a set of Hoosiers, and will give you one or two weekends of fun before they lose their stick. Again, I have no personal experience with them.

Ecsta V700 - These were new a few years ago, and I believe they were originally supposed to replace the Victoracers. Nevertheless, a friend of mine ran a set of 265/285 18" Ecsta V700's on a Boxster S with a very stiff suspension, and they blistered badly after a few runs. He thought it was a fluke, purchased another set, and was treated to the same blistering issue. He was very prudent in setting and monitoring tire pressures, etc. I've heard of others having this issue, and shaving is supposed to be a big help. There was an article in either Excellence or Pano a few years ago of a comparison between the MPSC's, Pirelli Pzero Corsas, and the V700s. The V700s blistered on them during the evaluation, and could not complete all of the tests. Some people run fine on these without issues. The experience I referenced above is from 2003, and I'm uncertain whether Kumho changed the "formula" since then. At the time, I felt the Ecsta V700s were fine up to ~8/10ths (unshaved) in the Boxster, then became squirmy after being pushed very hard.

Victoracers - Thought by many to be the best bang for the buck in the R compound family. They last a relatively long time and have good stick, but will not give you the laptimes of the Ecsta V710, any of the Hoosiers, etc. I have driven on a few sets of these and am happy with the results, but I realize it's a compromise tire. I drive to/from events, and I'm not looking for the last few tenths at the track, so they serve my purpose well.

Is this the info you're looking for?

[Craig 930 RS]

Thanks, K & MM -

This is the info I was looking for! Exactly.
Any other expeiences appreciated -

[ttweed]

According to the Kumho engineer I spoke with a couple of weeks ago, the major differences between the 3 tires you mention are the compound and tread design. Availability of appropriate sizes may effect your decision as well. The V700 is the hardest compound and comes with greatest tread depth. They do not need to be shaved, fall off the least over multiple heat cycles, and have the best performance in full wet conditions (but slowest in the dry.)

The Ecsta V700 is slightly softer and thus a little faster, comes with less tread depth but still should be shaved for dry track use and not be used in full wet conditions, but OK on a drying track with some standing puddles. It tolerates fewer heat cycles before falling off, and benefits from smooth driving (not exceeding 10% slip angle) to manage heat.

The Ecsta V710 is the softest of all, comes with only 4/32" tread depth, so does not need to be shaved, is the fastest of the three but cannot tolerate wet conditions at all. It should only be used at worst on a damp track with no standing puddles, and is the least tolerant of heat cycles (he specified only 3 before falling off noticably), requiring excellent tire management skills on the part of the driver to produce the best performance and longevity. You do NOT want to slide these tires around excessively, they will go off on you.

I tried the 710s for the first time this weekend and they have excellent grip, but I found I needed lower pressures than with the V700s to optimize the contact patch. After talking it over with one of their contract drivers, I am going to shoot for 27F and 30R hot pressures on my 2400 lb. 911 next time and see how it goes.

I find it interesting that Kumho is now getting into Formula 3 and ALMS racing, and expect to see the R&D from these efforts translate into a line of production racing slicks sometime in the future, to compete with the big boys in that arena, not just the DOT-R world.

TT

[Craig 930 RS]

Great stuff. Much appreciated -

[Craig 930 RS]

Rob & Tom -

How would YOU compare the Victoracers to the Toyo RA/1s?