Unique and exclusive models
It is not well known, that the 500 Miles of Indianapolis raced at the  famous oval circuit, was part of the F1 Drivers World Championship calendar between 1950 and 1960. Still, The specifications of the cars were very different, therefore, very few European teams went to compete on the other side of the Atlantic and very few, if any, of the American teams when to compete in Europe.
The most relevant participation of any European team happened in 1952. Ferrari decided to send some cars and his best driver at the moment, Alberto Ascari.
This is the single-seater built to race in the Indy 500 and the Ferrari technical staff had worked hard to reduce certain settings to comply with the rules for that race. Ascari drove it well on its track debut but even his considerable skills could not make up for the single-seater's lack of top speed and acceleration. The result was that it was fitted with four-choke carburettors, which combined with a ram-effect air intake on the bonnet, really did help boost its performance.
Some F1 single-seaters were modified (extended wheel base and engine with 4400 cc cylinder capacity) to have a go at the Indianapolis adventure. One car was assigned to Alberto Ascari for the 500 Mile race in 1952, which explains his absence from the Swiss GP on 18 May (won by Taruffi), because he was busy with the qualification trials for the American race.
Competing with the American cars, with a rougher design but perfectly suited to this type of race, was disappointing because Ascari had to withdraw with a broken wheel and the other cars, purchased by American drivers, failed to qualify.
The GP of the USA was introduced in 1960, and the 500 Indianapolis was taken out of the F! calendar forever.

1952-05-30 375 Indy (12) Alberto Ascari USA - Indianapolis R

1952-05-30 375 Indy (12) Alberto Ascari USA - Indianapolis R
It is not well known, that the 500 Miles of Indianapolis raced at the  famous oval circuit, was part of the F1 Drivers World Championship calendar between 1950 and 1960. Still, The specifications of the cars were very different, therefore, very few European teams went to compete on the other side of the Atlantic and very few, if any, of the American teams when to compete in Europe.
The most relevant participation of any European team happened in 1952. Ferrari decided to send some cars and his best driver at the moment, Alberto Ascari.
This is the single-seater built to race in the Indy 500 and the Ferrari technical staff had worked hard to reduce certain settings to comply with the rules for that race. Ascari drove it well on its track debut but even his considerable skills could not make up for the single-seater's lack of top speed and acceleration. The result was that it was fitted with four-choke carburettors, which combined with a ram-effect air intake on the bonnet, really did help boost its performance.
Some F1 single-seaters were modified (extended wheel base and engine with 4400 cc cylinder capacity) to have a go at the Indianapolis adventure. One car was assigned to Alberto Ascari for the 500 Mile race in 1952, which explains his absence from the Swiss GP on 18 May (won by Taruffi), because he was busy with the qualification trials for the American race.
Competing with the American cars, with a rougher design but perfectly suited to this type of race, was disappointing because Ascari had to withdraw with a broken wheel and the other cars, purchased by American drivers, failed to qualify.
The GP of the USA was introduced in 1960, and the 500 Indianapolis was taken out of the F! calendar forever.