For the 1979 season, Porsche officially only produced a handful of 935s powered by single turbo engines for the American market. Through the backdoor, the German manufacturer also supplied a pair of 935s fitted with the more potent twin turbo engine. Of these chassis 009 0030, delivered to Dick Barbour was the most successful. Sharing with Paul Newman and Rolf Stommelen, Barbour drove it to second overall at Le Mans in 1979. It then evolved into a 935 K3 and was later downgraded to 934 specifications, winning the Daytona 24 Hours and Sebring 12 Hours in these respective guises. Restored to its original guise, this hugely successful car has now been consigned to the Gooding Pebble Beach Auctions. The second example was sold to Bruce Canepa and he still races the car to this day in historic events.
At the recent Goodwood Festival of Speed, we were pleasantly surprised to see this Porsche 911 GT1 '98 restored to its original Zakspeed / Jever. In this guise, the car competed in the FIA GT Championship before it was returned to Porsche. It was then painted in the colours of the Le Mans winning sister car. As we could see at Goodwood, its period racing history is now reflected once more.
A couple of the Porsche's former rivals were also on hand. These included this Gulf Davidoff liveried F1 GTR Longtail. We last saw this car in North America when it failed to sell at the 2012 Bonhams Quail Sale but it does have a new owner now. Amazingly, a second Longtail was also on hand. This example was brought by BMW and finished in the familiar factory colours.

Enjoy the links:

1997 McLaren F1 GTR Longtail Chassis 28R - Ultimatecarpage.com

1998 Porsche 911 GT1 '98 Chassis GT1/98-004 - Ultimatecarpage.com

1979 Porsche 935 - Images, Specifications and Information