For motoring enthusiasts, finding secret concept cars from the past is as exciting as the discovery of a new species is for scientists.

Automakers rarely open their secret vaults, and when they do, it’s usually for select members of the media world, which makes Porsche’s move to share many of its hidden concept cars with the general public at the brand’s Stuttgart museum all the more special.

A total of 16 studies will be on display at the “Project: Top Secret!” on the following Sundays from 2:00 to 5:00 p.m.: Sept. 28, Oct. 19, Nov. 16, Dec. 14, Dec. 28, 2014, as well as on Jan. 4, 2015.

Among these cars are the 984 and 968 Roadster concepts, which in some ways, were the predecessors of the super-successful Boxster.

The 984 was a two-seater concept with a folding hardtop studied between 1984 and 1987 when the project was abandoned due to the sales crisis triggered by the sinking dollar.

Porsche says it was inspired by “a development job previously undertaken for the Spanish automaker Seat”. It was powered by an air-cooled, 2.0-liter turbocharged boxer engine capable of delivering between 120PS and 150PS stuffed in the rear end of the car. Not a lot of horsepower, but the Germans say it weighed a mere 880kg (1,940 lbs) and had a top track speed of 220km/h (137mph).

While the 984’s specs sound pretty solid, I can’t say the same about the styling, which with the top on, made it look a bit like a modern interpretation of the 914.

The 968 Roadster, on the other hand, is one handsome car in our book. Even if it’s essentially a modified 968 Convertible, the changes Porsche made, including the widened rear end and the lowered windshield and roof, work wonders on the shape. Heck, it still looks sweet today and it’s a pity it never made it to production.

We’re not sure if it’s included in Porsche’s special exhibit, but you can take a look at in the video below.

H/T to Motor-Klassik, Eric Lund and Auto-Forum!