997 GT3 RS 4.0: Porsche’s last stand?

You have to go back a quarter of a century to fi nd the origins of the Porsche 911 GT3, when sports car-racing at a world level more or less dried up with the demise of Group C.

It was Jürgen Barth, then Porsche’s competition manager, who together with Patrick Peter and Stéphane Ratel, conceived the BPR Global race programme based on production sports and GT cars.

In its fi rst season, the 3.8-litre 964 RSR dominated the fi eld, but within a year competitors had caught up. To succeed the RSR, Porsche developed a turbocharged version of the 993 in the GT2, which proved very effective in class B.

Porsche 997 GT3 RS 4.0 interior

However, producing a 996 successor in 1999 became more diffi cult: testing at the Nürburgring indicated that a turbocharged GT2 even with 600bhp would no longer be competitive.

It was inconceivable that Porsche could be without a racing presence, so Weissach turned to the GT3 production class as a lower-cost alternative. But building a competitive non-turbo 996 was also problematic: the new water-cooled M96 engine’s ‘integrated dry sump’ was really a wet sump, unsuitable for the lateral forces generated in racing.

Engine builder Herbert Ampferer devised a dry sump unit comprising a bespoke 24-valve cylinder head mated to the GT1 block, itself a derivative of the 964/993 bottom end. Technically, this unit was a success, with a 100bhp/litre potential.

Porsche 997 GT3 RS 4.0 dive plane

However, commercially Porsche would need to sell many more than the homologation minimum to amortise the development cost. Thanks to some lateral thinking by Ampferer and engineering director Horst Marchart, by deciding to use this new engine as the basis for the forthcoming 996 Turbo as well, volumes stretching into the tens of thousands would bring down parts costs and justify the design.

Enthusiasts recognised immediately that the road-going 996 GT3 launched in autumn 1999 had reignited the fl ame of the much-missed RS. Better still, while previous RSs had been lightened and fettled 911s off the line, the new 996 GT3 was a more rigorous conception built at Weissach from the chassis up.

To read more about the history of the 911 GT3 RS, including the ultimate culmination of the Mezger Rennsport line – the GT3 RS 4.0 – get you copy of Total 911 issue 115, in store, online, or via download, now.

Porsche 997 GT3 RS 4.0 rear wing

Comments (0)