Welcome to Car and Driver's Testing Hub, where we zoom in on the test numbers. We've been pushing vehicles to their limits since 1956 to provide objective data to bolster our subjective impressions (you can see how we test here).

Knobby all-terrain tires do not generally come with an on-road performance benefit. In fact, typically, it’s just the opposite, where improved off-pavement behavior means trading off on-road grip. But this common knowledge does not apply to the new and excellent 2027 Rivian R2, where the SUV’s 20-inch all-terrain tire option significantly out-grips the 21-inch street tire.

We were just as surprised as anyone when putting a second 656-hp R2 Performance—this one with the all-terrain tires, a $1000 option—through our testing regimen. These rollers resulted in its braking and cornering figures coming in substantially higher than the initial R2 we tested on its more street-oriented 21s. Wearing BFGoodrich All-Terrain T/A+ tires, the R2 clung on for 0.84 g on the skidpad, versus 0.81 g with the Pirelli Scorpion MS Elect option. Under braking, the differences were even larger, with the all-terrain R2 stopping in 166 feet from 70 mph and 320 feet from 100 mph, improvements of 12 and 43 feet, respectively.

This R2 was also fractionally quicker, rocketing to 60 mph in just 3.4 seconds and through the quarter-mile in 11.3 ticks at 128 mph (versus 3.5 seconds and 11.4 seconds at 128 mph), which is astonishingly quick for a brick-shaped small SUV.

These all-terrain tires also avoid the other typical bugaboo that often comes with blocky tread, as our interior-noise measurement at 70 mph was nearly identical. Both measured 67 decibels, while the R2 wearing 21s came in at 22 sones, versus 23 for the all-terrains.

Are these magic tires or what?

Well, the BFGoodrich All-Terrain T/A+ tires come in a variety of sizes, and every one of them—except for the R2’s—has a speed rating of either T (118 mph) or H (130 mph). But the Rivian’s are instead good for 149 mph (V rating). Every other version of this tire also gets branded with the three-peak mountain snowflake (3PMSF) label signifying elevated performance in snow, while the Rivian’s have a lesser M+S rating. The Rivian’s BFGs also have less tread depth, 10.5/32 versus 12.5/32 on all other variants. In other words, while the tires the R2 are wearing look like other BFG All-Terrain T/A+ rubber, there are quite a few differences, which no doubt contribute to the on-road performance gains.

The one area where the all-terrain tires behave predictably is in driving range. The R2’s EPA range is 330 miles with the 21s and 307 with the 20-inch all-terrains. But the difference in our 75-mph highway-range test was even larger: 260 miles for the 21-inch-equipped SUV and 220 miles with the all-terrain tires.

If we were ordering an R2, we’d probably go with the all-terrains, with their rugged good looks and improved on-road emergency response. Plus, the ride quality with the 20s felt a little better to our backsides too.

Specifications

2027 Rivian R2 Performance AWD Launch Edition Vehicle Type: front- and rear-motor, all-wheel-drive, 5-passenger, 4-door wagon

PRICE Base/As Tested: $59,485/$61,485 Options: Glacier White paint, $1000; 20-inch wheels and all-terrain tires, $1000

POWERTRAIN Front Motor: permanent-magnet synchronous AC, 294 hp, 254 lb-ft Rear Motor: permanent-magnet synchronous AC, 362 hp, 355 lb-ft Combined Power: 656 hp Combined Torque: 609 lb-ft Battery Pack: liquid-cooled lithium-ion, 88 kWh Peak Charge Rate, AC/DC: 11/230 kW Transmissions, F/R: direct-drive

CHASSIS Suspension, F/R: struts/multilink Brakes, F/R: 13.8-in vented disc/13.2-in vented disc Tires: BFGoodrich Trail-Terrain T/A+ 255/60R-20 113V M+S RIV

DIMENSIONS Wheelbase: 115.6 in Length: 185.9 in Width: 75.0 in Height: 66.9 in Passenger Volume, F/R: 57/53 ft3 Cargo Volume, Behind F/R: 79/29 ft3 Front Trunk Volume: 5 ft3 Curb Weight: 4997 lb

C/D TEST RESULTS 60 mph: 3.4 sec 100 mph: 7.1 sec 1/4-Mile: 11.3 sec @ 128 mph 130 mph: 12.5 sec Results above omit 1-ft rollout of 0.3 sec. Rolling Start, 5–60 mph: 3.7 sec Top Gear, 30–50 mph: 1.7 sec Top Gear, 50–70 mph: 2.1 sec Top Speed (gov ltd): 131 mph Braking, 70–0 mph: 166 ft Braking, 100–0 mph: 340 ft Roadholding, 300-ft Skidpad: 0.84 g

Interior Sound Idle: 30 dBA/1 sone Full Throttle: 71 dBA 70-mph Cruising: 67 dBA/23 sone

C/D FUEL ECONOMY AND CHARGING 75-mph Highway Range: 220 mi

EPA FUEL ECONOMY Combined/City/Highway: 99/109/89 MPGe Range: 307 mi

C/D TESTING EXPLAINED

Dave VanderWerp has spent more than 20 years in the automotive industry, in varied roles from engineering to product consulting, and now leading Car and Driver's vehicle-testing efforts. Dave got his very lucky start at C/D by happening to submit an unsolicited resume at just the right time to land a part-time road warrior job when he was a student at the University of Michigan, where he immediately became enthralled with the world of automotive journalism.

Extracted and lightly reformatted for readability. · Source: pt