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 Of
any single modification you can make to your vehicle-sports car, sedan
or even SUV-none offers more potential performance gain and bang-for-the-buck
improvement than getting shod with the right tires. Those four black doughnuts
are, after all, the only point of contact between you, your ride and the
road, and the best tire for any given conditions will mean shorter stopping
distance, crisper handling and in motorsports, the difference between
first place and everyone else.
Wait, you say, an accomplished driver will run rings around a neophyte
regardless of what they're driving and how it's been modified. True, so
we're going to assume you have already improved the driver by attending
one or more of the reputable driving schools, and perhaps you've even
taken the next step by participating in autocross or high performance
driving events.
For those not in the know, autocross is single-car at a time competition
on a parking lot or skidpad course defined by cones. The fastest through
the course without missing a "gate" or knocking over a cone
wins. (Check out the "solo" section at www.scca.com
for more info.) An HPDE is like road racing you see on TV, only it's done
with regular street cars on street tires, in graduated classes starting
with no passing and going through to unrestricted, pass-anywhere everything-but-who-won
road racing. (Check out the "HPDE" section at www.nasaproracing.com
for more info.)
Matching the type of tire to your particular use is key to making sure
you have the right tire. Being enthusiasts, most of us are primarily interested
in squeezing out that last bit of performance in dry conditions, be they
the street or track.
Yet even in performance tires, there are a multitude of made-up categories,
with the "top" category typically called extreme summer or perhaps
"maximum performance." Call it what you will, but tires at this
end of the spectrum must be able to deliver the highest degree of braking,
cornering and acceleration performance on the street and be suitable for
autocross or HPDE competition.
That's a tough category to play in, and there are only a handful of tires
fully capable of holding up to this sort of extreme use. We recently had
the opportunity to wring out a set of Nitto's new NT05 rubber, maximum
performance tires if there ever were any.
Nitto is a subsidiary of the Toyo Tire & Rubber Company, and since
Nitto doesn't have any mainstream OEM fitments don't feel bad that you've
never heard of this Japanese company.
Nitto has made a bit of a name for itself among enthusiasts by sponsoring
cars in the Formula Drift series. With the NT05, Nitto has set its sights
on providing a competitive tire for autocross, capable for HPDE and perfectly
matched for high-spirited street driving.
The NT05 carries a "W" speed performance rating, and its UTQG
rated at 200 tread wear, AA traction and A temperature. A large continuous
center rib and big outer shoulder blocks provide maximized tread contact,
while tread block reinforcing gives high speed stability.
We evaluated a set of NT05 tires in 265/35/18, mounted to 18x9-inch wheels
fitted to a mildly modified 2004 Subaru WRX STi. After just a few miles
of street driving it became abundantly clear that these tires are built
for a purpose-competition. They're relatively loud, very firm and transmit
every bump, pebble and crack through to the hands and to the tush. We
hadn't ever driven anything as stiff and responsive that wasn't
designed entirely for track use.
It was also obvious that there is no way to really test the performance
potential of the NT05 on public roads. Sure you can carve up a canyon
or two (we did), or go on your favorite corner, on and off-ramp hunting
drive (did that, too), but we're too responsible to take any real chances
in a public environment, so naturally we headed to the skidpad for some
autocross competition, where we could try out the Nitto tires to their
fullest potential.
Although there are more than 150 regular participants in the Arizona
Region's SCCA-sanctioned autocross events, the NT05 is not a commonly
seen tire-in fact, before we showed up to try them out they had never
been used by anyone in Arizona. We had confidence in them from
our street experience, though, and even had a suspicion they might be
faster than any other street tire (tires carrying a tread wear rating
of 140+).
With just four runs to get it done, our first attempt was reassuring-fastest
overall, including those on "R-compound" race tires. By the
end of the day the NT05's carried us to first among all street tire drivers
and second-fastest in overall "raw" time, just 0.215-second
behind a race-tire shod Viper. Not too shabby for the NT05's
Arizona debut.
A second event proved that the first wasn't a fluke, with another first
place finish in the street tire class though "only" ninth in
overall raw time-a fault of the driver's lackluster performance, not the
tires.
The NT05 provides tenacious grip, registering 1.04g on our Subaru's onboard
Passport G-Timer. Static grip isn't the end-all metric of performance
tires, however, and where the NT05 really shines is in transient response-saw
the steering wheel through a slalom and even a porky WRX STi turns in
crisply and right now. The NT05's stiff sidewall and carcass provide
maximum feedback through both the steering wheel and seat-of-pants, and
tread squirm under cornering and heaving braking is virtually nonexistent.
Breakaway beyond the NT05's limit is progressive and easily caught, and
even overdriving this street tire results in less punishing howl than
one would normally hear or expect. There is little squeal at the limit
as well, though not significantly less than any of the other tires in
the maximum performance segment.
Our competition driving experience confirmed what we thought would be
true after street driving-that the NT05 is a thinly disguised race tire
with enough tread depth and compound to make it a viable street-only tire.
It's telling too that our Subaru is no longer the only vehicle using NT05's
in Arizona autocross competition.
Though we haven't given them a full-life test, we'd expect to see around
20,000 miles on a set with no or limited autocross use (heavy autocross
and track use make mileage numbers moot-you have to pay to play, after
all).
In the rain the NT05 provides acceptable grip, though it's clearly biased
to dry pavement and for use only in temperatures above freezing (we wouldn't
recommend anything less than 40 degrees based on cold-weather degradation
in other maximum performance tires).
If you need for the ultimate in performance is clear, the NT05 is an
obvious choice that can put you at the head of your class. For more details
about the NT05, visit www.nittotire.com.
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