Ford RS200. Ferrari 250 GTO. Opel Manta 400. Chevrolet Camaro Z28. Dodge Charger Daytona. Mitsubishi Lancer Evolution. Porsche 911 GT1 Strassenversion. These are some of the most wonderful and soul-stirring vehicles we\'ve ever encountered, and they have one thing in common: They\'re all homologation specials, built and sold to the public solely so that their manufacturers could take even hotter versions racing. While some began as cars solely for homologation purposes, the marques took on lives of their own—witness the Evo and the Z28. The former is no longer campaigned in the World Rally Championship, while the latter went from a fire-spitting 302-inch monster in the late 1960s to a smog-choked key-party cruiser by the end of the 1970s. Others, like the Daytona and its near-twin, the Plymouth Road Runner Superbird, languished on dealer lots, sometimes for years. And some, like the RS200, never got a true chance to live up to their potential. Group B rallying was practically shot out from underneath the car before Ford had a chance to work through the car\'s first-season teething troubles. Porsche has not been one to shy away from building cars to suit a given set of rules. When the brand decided to contest Le Mans\' five-liter class, twenty-five 917s were constructed for eligibility\'s sake. We use “constructed” liberally, as there are rumors that Ferdinand Piëch\'s offer to the FIA inspection team that members were free to drive any of the 25 cars Porsche had built to meet the specification might\'ve been a bluff that he was hoping the inspectors wouldn\'t call. By 1972, a rules change had forced the 917 out of competition at La Sarthe. Figuring that there was still life in the old beast, Porsche added turbochargers to the car\'s flat-12 and went on to conquer the Canadian-American Challenge Cup. Nevertheless, Porsche wasn\'t done with sports-car racing in Europe. The company\'s next trick was less radical than the kill-everything-now sports prototype. Ferry\'s engineers took the nearly decade-old 911, punched out the 2.4-liter 911S engine to 2,687 cubic centimeters of displacement, added a ducktail spoiler, ballooned the rear arches to fit wider Fuchs wheels and scrawled “Carrera” down the side. The result was the 1973 Carrera 2.7 RS. The RS then spawned the even wilder Carrera RSR, which carries the amusing distinction of having a name that translates to “Race Racing Racecar”— Carrera” is “race” en español, while “RSR” stands for “Rennsport Rennwagen.” “Rennsport” means “racing” in German, and “Rennwagen” is, of course, \"racecar.\" The Race Racing Racecar was ultimately replaced by the turbocharged 934 and 935, which took the top four overall positions at Le Mans in 1979. Years ago, a group of automotive journalists—your author among them—founded an informal organization to promote awareness of the inherent greatness of brown cars. At the time, shades of the storied hue were found on very few manufacturers\' option lists. Porsche, however, had been keeping the faith. We noted at the time that practically any Porsche—save for the 914—looks wonderful in the shade. While Brown Car Appreciation Society members had seen later 1976-77 Carrera 3.0s done up in brown and had discussed how utterly, absolutely, unflinchingly rad a 2.7 RS in the hue would be, it felt like a mere daydream until we stumbled upon this particular machine. One of the first 500 RS cars built for homologation, this 2.7 is on offer at RM\'s upcoming Monaco auction. The 2.7 RS came in two flavors—a hard-core, lightweight variant featuring thinner glass and steel and a Touring specification that was designed to be more day-to-day liveable. This car was built to the latter spec, but we really don\'t mind, as we\'d be driving the thing all over tarnation. It\'s a 2.7 RS, the road-going 911 we covet most. It\'s brown. That\'s really all that needs to be said. If you\'ll excuse us, we\'re off to sell everybody\'s everything and hop a plane to Monaco. See you there on May 12. Please don\'t hate us for hocking your heirlooms. Prince Albert is already first in line for a ride in our new can, but we\'ll give you the second spin. We promise.