Editor’s Note: We first encountered designer Peter Stevens on Facebook earlier this month. We learned that longtime automotive designer was once involved with an Audi Le Mans project that pre-dated that of the R8R LMP1. At the time, Audi was exploring both the building of a supercar and the entry into Le Mans style sports car racing. GT1 & GT2 efforts were the hot formula at the time and the Audi TT was Ingolstadt’s only sports car.
Examining specs proposed, the car looked to be a radical undertaking. Had they been approved, both race and road versions of the G-TT were proposed to have a mid-mounted V8 twin turbo engine, 6-speed sequential gearbox, Brembo 4-piston brakes, OZ wheels, double wishbone inboard coil spring dampers and an aluminum and carbon monocoque chassis.
Looking back on the era, the Porsche 911 GT1 and Mercedes-Benz CLK GT1 are fascinating and incredibly rare examples of what could have been. Given all of this, we’re incredibly excited to have the G-TT (GT2) and TT GT1 story told in Mr. Stevens’ own words and augmented with design drawings, schematics and photos from the time period provided by the author.
[Begin story by Peter Stevens, subject: Audi G-TT and GT 1 Proposals]
Following a number of very successful years in the British Saloon car championship running first Volkswagen Golfs and then Audis, Richard Lloyd and I had a plan for a Le Mans eligible GT2 Audi, tentatively called G-TT. I made a number of design drawings as part of a proposal to Audi that was presented in January 1997 for the 1998 season. This was before we carried out a much bigger research study for an Audi GT1 project called R8 GT that later became the Le Mans R8 project. There was a package layout for the G-TT and a specification page from the report document which is attached. Audi’s road-car division, under Doctor Ulrich Hackenburg, were working on a mid-placed V8 engined version of the new front-engined TT. We had the opportunity to do some laps of Audi’s short test track as passengers in the car, late in 1996.
The idea for the G-TT was that it should look similar to the current TT but have a much greater road presence and a layout that would have made a very competitive GT2 race car. The engineering was looked after by Jim Router and Gerry Booen, both ex-Lotus guys; the overall project direction came from chief designer Nigel Stroud. I was in charge of aesthetics and aero development as well as presentation content for our Audi meetings at Ingolstadt.
The next logical step beyond the Audi TT based GT2 was to consider a GT1 Le Mans car. The McLaren F1 GTR had shown that a GT1 car could compete for overall victory at Le Mans, therefore a more race car oriented GT appealed to Audi.
Work started on this project towards the end of 1996 and by February 1997 a complex wind tunnel development programme was underway at the Activa rolling road tunnel. This tunnel had previously been the Brabham Team aerodynamic facility, at the time it was available and comparatively inexpensive but perhaps not with as much repeatability as we would have liked. 550 runs were carried out with more than 50 variations of concept under the direction of designer Nigel Stroud, engineer Jim Router and myself.
The objective was to find a good efficiency for the car, this required not only the development of reliable downforce but also low drag. We were looking for a lift over drag, L/D ration of about 3.20. From an acceptable race-car base line we then worked back to produce a road-car specification that gave an exciting looking customer car with plenty of opportunity for development. This was more in the manner that Mercedes and Porsche worked than the McLaren F1 which started out as a pure road-car that was later developed for racing.
In parallel with the aero development we produced a full size side view tape drawing, a full size seating buck and a design presentation for senior Audi personnel, which included CEO Franz Paefgen, motorsport chief Wolfgang Ulrich, head of engine development (a good friend) Ulrich Baretzki and design chief Peter Schreyer.
The project, codenamed ‘Aurora’ was intended to become the Audi GT1 R8 but during 1997 it became evident that the new category for Le Mans Prototypes, LMP was where future winners would come from. As well as all the engineering development proposals Richard Lloyd presented a very complete business plan for the GT1, this undoubtedly caught the eye of Doctor Ulrich who could see the possibilities of a long term project for his Ingolstadt based team.
Richard Lloyd’s group went on to develop the Audi R8C for the 1999 Le Mans 24 hour race under the design direction of good friend Tony Southgate whilst I worked with Williams and BMW to produce the LM99 winning car. The R8C was a good looking car but I suspect that the Audi factory effort was more focused on their own R8 open car, the first of a series which continue to dominate Le Mans.