[TCracingCA]

Both the 2.7 RS and the 2.8 RSR were homologated into racing independent of each other. One ran initially because of the number built Group 4 rules (2.7), and Group 5 (2.8). They were completely different animals!!! The 2.8 RSR was another bullet preloaded into the gun and ready to shoot, in anticipation of what the organizers would do next. And thus Porsche had the bullet to counter!!!!!

The first Turbo to be put into production technically was the 1975 Porsche Carrera Turbo and not the 930. Thus this would be the first of it's breed and the 930 is technically an incorrect answer!

The 917 was not replaced, it was outlawed by rules out of Competition. Thus the only thing Porsche had to field in the new Group 6 format was the Porsche Turbo 911 cars. They purposely were $crewed by the French and French controlled (at that time) FIA Organizers. Porsche was exploring a future with the 917/30 and that model was not Porsches creation, but Penske's and the expansion of the Interscope Series was thought to be the place to be and the future. Then the oil embargo's and a high profile of 1000+ hp (non green!) bad for the Company imagine took effect and changed racing at that period. Thus that is the one of the few times that Porsche got caught out!!!! The Race 911 Turbos were small displacement and with the new Turbo technology, so Porsche thought it would be good for their image! The Carrera programs were then developed as an offshoot of the chassis development and not the engine technology! They thought they were years from developing Turbos for the street and that prediction was accurate. The reliability was just not there yet! Also in competition the other Manufacturers were screaming foul! Thus this all led to making and fielding a more pronounced Production based appearance. Then with the advent of the 936, that was considered a leading edge developmental Prototype and the concentration went to moving that technology into the 935 and down the chain to a Production available Turbo. Thus Porsche helped their public image by sticking with the 936 program claiming developmental with limited entries and no privateer sells 1976-78. Porsche then grew tired of non-Production models being allowed such as Lola and such and then built the 956 to the loophole in the rules. Then IMSA basically outlawed that, so they countered with the 962!

I could keep pluggin in history between each sentence, but this is the summary of what happened!