NT555RII

About the Nitto NT555RII

D.O.T. Compliant Road Race Competition Radial tire designed with the Muscle Car Racer in mind.

Features

* Semi slick shoulder block design* Specifically designed sidewall construction* High modulus polyester carcass, reinforced sidewall and semi-radial body construction* Road race compound

Benefits

* Minimizes heat build up and maximizes cornering grip and turn-in response* Increases steering feedback and precision for driver confidence* Increases stability during braking, cornering and straight-aways* Balances dry traction, consistency, heat cycle performance, heat resistance and longevity

Understanding the P315/40R18 size

In the size code 315/40R18, 315 is the section width in millimetres (about 12.4"). 40 is the aspect ratio — the sidewall height is 40% of the width, or roughly 126 mm. R18 means radial construction on a 18-inch wheel, giving an approximate overall diameter of 27.9".

The load index 102 means each tire supports up to 1,874 lbs — about 7,496 lbs across a full set of four. The speed symbol W certifies the tire to 168 mph under its rated load. Always match or exceed the load index and speed rating listed on your vehicle's door-jamb placard.

Tread life and grip ratings

This tire carries a UTQG rating of 100 A A. The treadwear grade of 100 is a relative durability score — a grade of 200 is expected to last roughly twice as long as a grade of 100 under the same controlled test. Traction grade A measures straight-line wet stopping grip (AA is highest, then A, B and C). Temperature grade A reflects heat resistance at sustained speed (A is highest).

Price and value

At $377.25 per tire, a full set of four costs $1509.00. That is about 30% above the average of the 4 tires we stock in this size, reflecting its position in the range.