This 1985 Pontiac Firebird Trans Am (VIN 0000EX4796) is a one-off factory Kammback concept that was once used as an auto show circuit promotional model. Following a tour of US convention centers, it was mounted with a light bar and pressed into IMSA pace car duties before ending up in Pontiac’s Engineering Car Collection until the late 1990’s. At this point it was reportedly purchased by a local marque dealer and collector who is said to have restored the car in “meticulous detail.” Find it here at Barrett Jackson who will oversee its no-reserve auction in Scottsdale, Arizona.

GM flirted with F-body Kammback concepts on and off for a while, and these third gen examples were particularly interesting for the way the base design’s glass hatch more easily accommodated what was in essence simply a redesigned tailgate section. The seller reports that a previous owner restored this car, but it’s not quite clear what work was needed.

No interior or engine bay shots are provided, but power is reported to come from a 5.0/5-speed combo. There’s no word on mileage either, and the car is sold on a bill of sale–its prototype status means it probably can’t be registered, either–at least not easily.

Here’s a promo shot of one of the division’s earlier Kammback concepts, showing off neat side-opening twin glass hatches that appear to have been omitted on the later example at hand.