Rubuta ci gaba don wannan sakin layi - Mathieson ya shiga ERA E-Type tare da Leslie Johnson a matsayin direba, don 1949 Richmond Trophy, Jersey Road Race da British Empire Trophy, da kuma 1950 British Grand Prix
Ka yi haƙuri. Wasu kafofin suna danganta waɗannan a matsayin shigarwar ERA na hukuma saboda Johnson ya sayi masana'antar kera motoci shekaru uku da suka gabata. Mathieson ya sayi Frazer Nash Le Mans mai lita 2 wanda a ciki ya ci nasarar aji a cikin Sa'o'i 24 na Le Mans na 1950 tare da Richard "Dickie" Stoop.