First, the boring part. The Porsche 935 was the penultimate 911 for Group-5 rules. Now the exciting part. The Porsche 935, built using 'sillhouette' rules and loopholes, allowed anyone to build their own dream special customer variant. The penultimate version was not the 'Moby dick', it was the JLP-4.
John Paul and his son, John Junior, Had created the winningest 935 ever, the JLP-3 and felt they could do one more. They build the JLP-4. It would have an uncorked big boost 3.2 liter engine and also become the first and only 935 with ground effects.
These 'specials' were the silhouette cars built on what was barely left of a 911 shell. In this case, there was no longer a shell. The bodywork presented somewhat of the original look but in all reality it was a Porsche powered funny car for a road course.
The Group-5 rules allowed the floor pan to be cut away for exhaust clearance. that rule was allowed mostly for BMW to boost their 3+ liter sixes, but Porsche used it too cutting away all of their floor and having a shell sit over three inches lower. The Pauls built the driver position as close to the center position they could, built it with Can-Am suspension and flipped their transmission upside down to lower the trans-axle shafts and with a flat fan twin turbo engine producing 850hp of dirty fuel-rich exhaust they thought a trip to the Lockheed wind-tunnel to tune some ground effects in there would do the trick. The end result, off the trailer, was two wins in the first three races beating Prototypes. It was four seconds a lap faster than the JLP-3 at Road Atlanta. A sprint race weapon.
Here is The JLP-1 in car during it's Huntington Disease awareness tour.