First, there was Nitto's NT555R Extreme Drag radial, a ground-breaking DOT-approved tire for street and strip. It set new standards for street traction that many other companies have tried to duplicate. Then Nitto introduced the take-no-prisoners NT1320 drag slick, a full-on competition tire that aimed to set new traction and stability parameters for professional drag classes. Now on the heels of the NT05 Ultra High Performance summer tire, Nitto is releasing a companion drag radial with an aggressive compound. Not only does it offer more grip than the 555R Extreme Drag, but it is also a cosmetic match for the NT05, allowing enthusiasts to "dress" their vehicles correctly with similar appearing high-performance rubber front and rear.
We recently got a pair of the NT05Rs and mounted them on our '68 Chevelle project car. Our 275/40R17 test tires arrived right off the jetliner from Japan, and were among the first production examples of the new breed. We immediately checked the treadwear rating and discovered it was "00," compared with the 555R Extreme Drag's "100" rating. Although the expected tread life is less on the NT05R than the 555R, the trade-off is greater grip at the track and that's what we were after with our 600-plus horsepower big-block Chevelle.
The tread design is cutting-edge modern, and mimics that of the NT05 Ultra High Performance summer tire-the only difference in appearance is that the tread blocks on the NT05R are larger, and have less void between them. Both the NT05 and NT05R feature a meaty patch of uninterrupted rubber in the center for outstanding grip. The primary means of fluid draining in wet weather are two grooves on either side of the center tread. These grooves are flanked by substantial tread blocks at either shoulder, larger ones on the NT05R. According to Nitto, the rubber compound on the NT05R is significantly softer than the NT05 (which has a treadwear rating of "200" versus the NT05R at "00"). Also, the sidewall construction of the NT05R has been optimized for drag racing, and features additional compliance for launches, and a different internal construction in the cap for high-speed stability down the big end of the track.
Nitto plans to offer the NT05R in seven sizes, starting in January 2010. These will range between 17- and 20-inch in rim size (see chart elsewhere in this story), making the NT05R the first drag radial ever offered in a 19-inch size. For early muscle cars, the current assortment of 17- and 18-inch NT05Rs should cover a wide array of cars, including '64-72 GM A-bodies like our Chevelle.
We took our fresh pair of NT05Rs over to Big O Tires (a local Nitto dealer) in Moreno Valley, California, and had them mounted and balanced on our 17x9 Vintage Wheel Works V40 rims. It's worth noting here that we had been running Nitto's race compound NT01 at all four corners of the Chevelle, and with the NT05R in back and the NT01 in front, we were surprised at how well they match cosmetically. In terms of grip, the NT01 is closer to the aggressive compound of the NT05R than the standard NT05, so our handling will be minimally affected at the limit.
With the NT05Rs mounted, we drove out to the Street Legal Drags in Fontana, California, the following weekend. Unlike our East Coast brothers at Super Chevy and Muscle Mustangs & Fast Fords, we didn't have the luxury of unlimited testing at an empty track; we had to endure nine hours of waiting to make just two passes down the quarter-mile, which is more along the lines of what a typical reader would encounter. We arrived at 5:30 a.m., only to find there were already 200 cars in line ahead of us. Oofa! After teching in, we puked the contents of the Chevelle in the pits, and got into the staging lanes. Five hours later, we made our first run. With the tire pressure set at 30 psi, we performed a super smoky burnout, and staged up. Not wanting to launch as aggressively as we normally do with the Mickey Thompson 10.5x28 slicks, we only flashed the converter to 1,500 rpm on launch. That still managed to elicit huge amounts wheelspin and lots of wasted time. The timeslip read a disappointing 12.90/112.7 with a 2.39 60-foot time.
The Nitto NT05R is a max-effort, street-legal drag radial with a treadwear rating of "00." Although it looks similar to the NT05 Ultra High Performance street tire, its design has been optimized with a compliant sidewall for good launch characteristics, and a different cap configuration for stability at the top end of the track. Nitto will offer the NT05R in seven sizes initially, including a 345/30R19 and 315/35R20.
Lots of tire pressure (or at least "street" pressure) is clearly not the way to go with the NT05R. With 700 cars in the pits and one big oildown on track, we couldn't afford to mess things up again, so we went big. We deflated the NT05s to 15 psi, and got back in line. Four hours later, it was finally our turn to make our second-and last-run. After another huge burnout, we staged and brought the engine up on the converter as high as we dared-about 1,800 rpm. We took our time launching on the green, and marched through the gears of our TCI Super Street Fighter Turbo 400 manually with our TCI Outlaw shifter. We came out of the hole at less than full throttle, and by the second gearshift, we were able to lay it fully on the wood for the rest of the run. It's worth noting that the 496 big-block felt incredibly healthy with its new COMP short-travel lifters, and our Howitzer 496 big-block was still pulling strong through the lights at 6,000 rpm. The result: an 11.80/116.7 with a much-improved 1.87 60-foot time.
As a point of reference, the best ever e.t. the Chevelle has gone is an 11.30/116.9 with a 1.57 60-foot time. This was with Mickey Thompson 10.5x28 ET Drag slicks, and Sportsman Pro skinnies up front. With the NT05Rs, we're still over three-tenths off our best 60-foot time of 1.53, but with a little more practice and a further reduction in tire pressure, we think we can whittle that down into the 1.70s or even high 1.60s. If we can do that, we should be able to e.t. somewhere between 11.50 and 11.60. For now, though, we're ecstatic that the Street Sweeper Chevelle is capable of deep 11s in 100 percent street trim, and that's the whole point of the NT05R. There's clearly a lot of untapped potential in this tire, and we plan to probe the limits further if we can get some more track time.
We took the test samples Nitto gave us to Big O Tires in Moreno Valley, California. Big O is a dealer for Nitto, and did a fine job mounting and balancing the NT05Rs on our Vintage Wheel Works V40 alloys.
Based on our initial results, we'd highly recommend the NT05R for the guy who wants ultimate grip in his street car. They handle well on the road-unlike bias-ply DOT cheater slicks-and can greatly simplify your trips to the track. The NT05R will get you 90 to 95 percent of the way there without the expense of extra rims, tires, tubes, screws, trailers, or tow vehicles, and the NT05R can do double duty for daily driving in seasonal weather (i.e. all the time here in California). We like them so much, we'll be keeping the NT05Rs on the Street Sweeper Chevelle indefinitely. There's a lot more left in them!
NT05R SIZE CHART TIRE TREAD DIAMETER: WIDTH: APPROVED SIZE: DEPTH: RIM WIDTH: 275/40R17 6/32 25.79 11.02 9.0-9.5-11.0 315/35R17 6/32 25.71 12.48 10.5-11.0-12.5 285/40R18 6/32 27.09 11.42 9.5-10.0-11.0 305/45R18 6/32 28.9 12.05 9.5-10.0-11.5 315/40R18 6/32 28.03 12.6 10.5-11.0-12.5 345/30R19 6/32 27.36 13.43 12.0-13.5 315/35R20 6/32 28.74 12.74 10.5-11.0-12.5