At first it looked as though the Italian teams had stolen a march on the British Grand Prix teams, by being ready for the 1958 season and getting to the Argentine in time for the first round of the World Championship. Both Ferrari and Maserati cars took part in the Argentine Grand Prix, while Vanwall and B.R.M. did not, and only a lone Cooper-Climax represented Britain, but, in actual fact, there was only one new car in the brief entry of 10 machines that took part in the race, this being one of the Ferrari entries, the other nine cars all being 1957 machines.
Collins and Musso drove the two V6-cylinder Ferraris that ran at Modena and Casablanca last year, while Hawthorn had the new one; though new in construction it was not new in design, being as the other two, with large-tube ladder-type frame with small-tube superstructure, the new design of chassis not being completed in time for this race. Among numerous small modifications made to the cars since Casablanca, Hawthorn’s model had experimental brakes, which proved to be too powerful, causing frequent wheel-locking, and an aero-screen in place of the normal wrap-round Perspex one. The three lightweight chassis Maserati cars used by the factory team in 1957 had new owners, two of them being bought by Fangio’s Scuderia Sudamericana, and the third by the Australian racing motor-cyclist, Ken Kavannagh. The other three Maseratis in the race were the old ones of Godia and Gould, and a similar old one borrowed by Schell. As Behra was without a car, Kavannagh lent him his car, and delayed his motor-racing debut for a couple of weeks, rather than see a potential winner standing on the track-side. To complete the field of ten there was the R. R. C. Walker Cooper, driven during last season by Brabham; this car being a slightly stronger version of the Formula II chassis, with various modifications to suspension and cockpit cooling, and fitted with a 1,960-c.c. Coventry-Climax engine. With no proper Grand Prix car at his disposal, Moss agreed to drive the little Cooper, and it was rushed to the Argentine at the last moment, the Italian cars having gone from Genoa in mid-December.
Fangio and Menditeguy drove the Sudamericana cars, the World Champion taking his choice after trying both of them, and, apart from alterations to compression-ratios and carburation to suit the straight 130 octane petrol, they were virtually as raced last season by the factory. In spite of the change of fuel, practice lap times were as fast as last year and there was little to choose between Maserati and Ferrari by the time practice had finished, less than one second covering the first five, who were Fangio, Collins, Hawthorn, Behra and Musso.
