Automaker could have sold more cars in the U.S. but inventory levels were very low, CFO Katsuyuki Mizuma said.
Subaru's output fell 20 percent to 207,000 in the quarter, while deliveries plummeted 35 percent to 173,000 in the same period.
The automaker's motorsports division will test the car at circuits in Japan and try to set a new lap record on Germany's famed Nürburging from 2023.
Japan's automakers are stoking R&D investment to meet mounting demand for a staggering array of technologies. Toyota by far outpaces the pack.