This car is so rare that enthusiasts debate whether it actually exists. There is no such thing as a factory-built Firebird with 428 engine. But this was the 1960s, a time when it was normal to have your local dealer or mechanic sell or build you a race car which you could then drive on the track, on the street, or both. If you don't believe me, watch the movie
Two-Lane Blacktop.
The Firebird 428 was a 'conversion' offered by a dealership called Royal Pontiac. The car got enough attention that
it was featured in Motor Trend, and at least one other dealer copied the idea. That black thing on the hood is Pontiac's
hood tachometer, because when driving a car like this you need to have your eyes on the road, not the dashboard.
Update 6/30/18: I met the owner of this car today, and this is NOT a true 428 Firebird; it has the engine and 428 badges from a '69 Bonneville.