Porsche weight-saving

Sir,

I have just beat reading the article “Germany’s Championship” in Motor Sport of September, page 1120, in which surprise is expressed about the saving in weight from which the Porsche 935/2.0 (the “Baby” as they call it) has benefited, compared with the larger engined car.

The greatest part of the saving is explained in the FIA Yearbook, page 179, art. 289 b, where you can read: “No modification may be made to the series (read standard) coachwork and/or the original chassis and bodywork, except as regards lightening of the structures by removal of material and the adjunction of chassis reinforcement.

Though this was certainly not what those who wrote the rules had in mind, the wording can mean that you may remove practically anything from the original structure and replace it with something else.

With a minimum weight of 970 kg. imposed by the rules (art. 289 a) for cars of technically up to 4-litres capacity, the standard body shell could be kept more or less intact for the 935/2.8 and thanks to the weight saved in many other places, the car must still carry some ballast, located in the best possible position to improve the handling (more than 100 kg. lead was carried by last year’s car which did not have the long tail added). In contrast, the 935/2.0 for which the minimum imposed weight is 735 kg., carries no ballast and a lot of further weight has been saved cutting off the original structure fore and aft of the front and rear bulkheads and replacing it with aluminium tube subframes, as had been done in the 2.1 litre Turbo-Carrera of 1974. Apart from this, the wheels and tyres are lighter (maximum width rules) and the smaller engine needs only one turbocharger and one waste gate.

Anyway, when one remembers that the original idea of Group 5 was to race basically production cars and keep their appearance close enough to the standard model for easy identification, it is quite obvious that the whole thing has got completely out of hand, mainly due to the haphazard wording of the rules. The cars would all look much different (which say they are “free”) if the words “wheel openings” had been used in the rules (which say they are “free”) instead of “wings”. The wings (those the Americans call fenders) are not a separate entity in modern cars anyway.

And thanks for the excellent report on the Grosser Preis von Deutschland!

Vence, France – Paul Frère