Saw a very unique 911 at a restoration shop today.
This 1974 Carrera (1 of 200) was purchased new at Brumos. The owner asked for more horsepower. Porsche had available at the time an RSR engine kit, of which apparently six were sold. So this car had the 2.8 RSR engine and transmission installed as well as Recaro leather seats. Approximately 300 HP. Fate of the other five kits appears to be unknown. This car has all paper work from day 1 and is undergoing a thorough restoration in the USA. Sorry for the crappy photo.
No muffler, just straight pipes.