Sometimes, motorsports rules force automakers to sell certain vehicles to the public to homologate their racing machines for competition. The results are generally cars that set enthusiasts' hearts aflutter, like the Porsche 911 GT1, Lancia Stratos, and Dodge Charger Daytona. This pristine 1979 Datsun 280ZXR that Mecum is auctioning is a less famous, yet still fascinating, vehicle built to ensure a very specific piece of bodywork could qualify for racing. And you can own it.

The 280ZXR was only available for the 1979 model year, and Datsun (now Nissan) made between 1,001 and 1,009 of them, depending on what source you believe. The company wanted a larger rear spoiler for the Z-cars racing in IMSA and SCCA competition, but the piece had to be available on production vehicles for that to happen. This limited-run model was the result. 

Gallery: 1979 Datsun 280ZXR Mecum Auction

While reasonably modest looking, the enlarged rear spoiler allegedly made around 400 pounds of downforce at 100 miles per hour. This piece helped keep the car planted to the track while racing. The part worked because the Electramotive team won nine of the 15 races in the GTU class in 1979.

Z-car fans could also buy the spoiler from the Datsun Competition Parts Catalog, according to the specialist parts seller Xenon Z Car. It came as part of a kit with heavy-duty rear hatch struts.

St. Yves Motor Sales in Berkley, Massachusetts, took delivery of this 280ZXR in the late 1970s, performed an inspection, but never sold it. Today, the odometer shows a mere 15 miles. The sale even includes a spare OEM stripe kit, the original window sticker, and a dealer information sheet.

All 280ZXRs came in a Silver Mist body with blue stripes on the hood and flanks. The exterior and interior appear to be in pristine condition.

Under the hood, there was a 2.8-liter inline-six engine. Unfortunately, 1979 was still deep in the malaise era, so the power plant made just 135 horsepower and 144 pound-feet of torque. The power routed to the rear wheels through a five-speed manual gearbox. Given this car is over 40 years old, all of those rubber vacuum hoses might need some attention if the new owner intends to drive this vehicle.

Mecum doesn't offer an auction estimate for this 280ZXR. However, the car is available with no reserve, so someone might be able to get it for a bargain.

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