ðə pˈɛtɹəl dʒˈɛt ˈɔːɹɪfɪs ænd ðɪ ˈɛɹ səplˈaɪ θɹˈɑːɾəl ˈoʊpənɪŋ wɜː dɪzˈaɪnd tə kˈʌvɚ ðə hˈoʊl ɹˈeɪndʒ ʌv spˈiːdz.
The petrol jet orifice and the air supply (throttle opening) were designed to cover the whole range of speeds.