My 1st 911, a sub 20,000 mile preowned 1984 Carrera Targa. It had been owned by the chief engine builder/engineer for the Chaparral Can Am and then Indy Car race team. I was told he took the entire drivetrain apart when he took delivery new and went over every part in order to "improve". Improve he did! It was so smooth and easy all the way to redline, which was about 500rpm higher after his touch. It wailed like a Ferrari. When I moved to another town and took it to the Porsche dealer there for some routine service, the entire service team and some of the management were waiting. It was only then that I came to understand how special that car was. The Fuchs wheels has a personalize engraving the the original owner inside each rim. It was explained to me that that particular 911 was built special and to the tightest tolerances they had ever seen. It was a street Porsche built by their racing team. I'll never forget that car...sold it to fund grad school...I dont recall if I met the buyer or not but it sold to the first caller full pop, then onto a trailer.