The first Porsche saloon you see pictured on your right hand was based on the late 1960's 911. It was a one-off custom creation built by California coach builder Troutman-Barnes with the blessings of Porsche.
It is claimed that the eerie-looking sports saloon with the rear suicide doors and the four-seat layout was crafted by conjoining two crashed 1967 911s.
In the mid-1980s, Porsche and AMG (then, an independent company) developed a fully working prototype of a four-door 928 S4 that could be viewed today as the Mazda RX-8's forefather. It featured an extended wheelbase, half-sized suicide rear doors and looks that kill - literally...
The bizarre-looking 1986 928 S4 saloon was delivered to the founder and CEO of American Sunroof Corporation (ASC), Heinz Prechter. In August 2002, the car was changed hands at the RM Monterey Auctions for $44,000, or $1,000 less than the low estimate.
And last but perhaps not least as there may be another custom built or concept Porsche sedan that we are not aware of, is the 989 prototype that was created under the watchful eye of Dr. Ulrich Bez, now in charge of Aston Martin.
Quite possibly the closest relative to the Panamera, the V8-powered 989 sedan project kicked off in the late 1980s but was terminated in the early 1990s as falling sales of the 928 made Porsche rethink the idea twice. Even though the Stuttgart-based automaker initially said that the concept model had been destroyed, later on, officials claimed that the 989 remains in storage hidden away from prying eyes.