NT555 G2 Review: Getting Grip in a 900hp Supercharged S550 Mustang

• September 7, 2021
• Story By
  Andy Carter

For every project that has started off as a purpose-built race car, there’s at least twice the amount that started off as a daily with “just a few mods.” This 2018 Mustang was meant to be a mild cruiser, but the owner got bit by the more-power-bug and dove headfirst into the build, ending up with a Whipple supercharged V8 making over 900hp and running a 10.6 second quarter mile. Following the lead of many Mustang owners, he installed a set of Nitto NT555 G2 tires on 20” KMC District wheels with a pair of 255/35/20s at the front, and 305/30/20s at the rear.

As Nitto’s entry in the ultra high performance summer tire category, the tires have performed well for the demands of the boosted Mustang. While this S550 no longer serves as a daily driver, it is far from a track toy, and needs to function as a street driven vehicle. The NT555 G2 excels at that balance, navigating the sometimes complex, sometimes competing needs of a high performance street car.

Grip When You Need It

In Georgia, where snow isn’t much of a concern, the biggest environmental hazard for a performance car are surprise rain showers. During the summer, a weekend trip to a local Cars and Coffee event in the morning can quickly turn into a slippery drive home without much warning. The NT555G2 was designed with center and shoulder grooves that aid in water evacuation and wet handling, giving owners confidence to handle errands during inclement weather.

OEM Drivability

From a comfort perspective, the Nittos were better or equal to the OEM-equipped summer tires. Road noise is a minimum, and the rubber absorbs road imperfections and bumps especially well for the larger diameter sizes. While Mustang owners in areas more susceptible to harsh conditions might benefit from an all-season design, for those with more mild weather (especially for a hobby car), an ultra high performance summer tire is a better choice for an enthusiast driver.

For a high-horsepower car, however, grip will always be an issue. Luckily, this particular Mustang has been tuned to come alive higher in the powerband, with a predictable, smooth curve. Driven responsibly by an experienced driver, the Nitto NT555G2s deliver that power to the ground reliably and effectively. The large tapered tread blocks and twin center ribs keep the pony car glued to the pavement under spirited driving, in the straights or curves.

What If You Need More Grip?

The temptation, of course, will always be to push the car into those last few degrees of performance. At 10/10ths, the 900hp in this particular application simply pushes past what the NT555G2 was designed to handle in many situations. For track performance especially, the limits of a summer performance tire are evident under full throttle bursts.

NT555RII Solution

Luckily, Nitto has designed a tire combo for these specific situations. The Nitto NT555RII D.O.T.-compliant competition drag radial was created for the weekend-drag racer to pair with the NT555G2 for street driven vehicles. By running the more conservative summer tire up front with the NT555RII on the driven axle, owners can push their cars even further. When developing both product lines, Nitto matched the tread pattern and sizing to fit modern performance vehicles.

Any issues with grip are handled with the installation of Nitto’s drag radial at the business end of the Mustang. The high-grip compound and semi-racing construction provide increased traction at the starting line, while the large circumferential grooves aid wet handling around town, or on the way to the race track.

The trade-off, of course, comes with a ride significantly more tilted towards performance than comfort. Compared to a summer tire, the NT555RII will be stiffer and louder, and will wear faster. For a high horsepower car, however, the gains at the limits, and even below, are significant; improved grip means improved confidence, which ultimately leads to a better driving experience on those weekend trips to the mountains or track, or just around town.

Are Drag Radials Right For Your Car?

Ultimately, the decision to incorporate drag radials into a tire/wheel combo is up to the owner, and largely dependent on driving style, and perhaps more importantly, power levels. For stock vehicles, or mild tunes, the NT555G2 at all four corners is ideal for the vast majority of owners. For those that want to push the limits of the chassis however, and have the luxury of another vehicle for daily driving (or maybe can tolerate the drawbacks of such a setup), a set of NT555RII wheels in the rear can unlock another level of performance capability in the S550 Mustang.