HOW CLOSE IS IT?

PORSCHE'S 911 GT3 RS GOES HEAD TO HEAD AGAINST A 911 GT3 CUP RACE CAR AT ROAD AMERICA

- MAC MORRISON

After our first drive last fall of the new Porsche 911 GT3 RS on the U.K.’s Silverstone circuit, we suggested a need for “a new metric for evaluating cars like this. Sure, the GT3 RS will produce solid figures in our traditional testing, from 0–60 and quarter-mile times to braking distances to skidpad g’s. But none of those things is what this race car level of capability is about, and they’ll do nothing to accurately express the reality here.” As Porsche GT division boss Andy Preuninger told us at the time, “This car, on high-speed corners with a Cup-R-rated street tire, is quicker than a 911 Cup race car on slicks. Not in every corner but in [some] high-speed corners. For a street-legal car this is a serious, serious statement.”

Why Are We Doing This?

To Preuninger’s point, fast cornering is the name of the game in this mindbending era of big-downforce road-legal performance cars, and if you’re lucky enough to drive or ride in one at speed on a proper circuit, you immediately feel the phenomenal cornering grip and braking. Chances are, after just a lap or three, you’ll understand and never again question what the fuss is about. It’s a type of performance not captured in straight-line acceleration and braking tests, and neither is it given anywhere near its due by measuring lateral g’s during