Kammala wannan jumla: Simon ya fara tsere a 1970 yana tuka motar Vollstedt ta hannu a Phoenix International Raceway amma ya yi kasa a gwiwa saboda matsalar magnet bayan kawai 4 laps. Ya yi nasa
Indianapolis 500 ya fara wannan shekara kuma ya gama matsayi na 14. A Ontario Motor Speedway a watan Satumba, Simon ya kama aikinsa mafi kyau na 3rd kuma ya gama 10th a 1970 USAC National Championship. Simon zai ci gaba da kasancewa mai gasa a cikin shekarun 1970, ba zai taɓa daidaitawa da kammalawa na 1970 ba. A cikin 1979, Simon ya kasance tare da USAC yayin rabuwa da CART. Kasancewa ɗaya daga cikin driversan direbobi kaɗan don kammala jadawalin USAC, Simon ya gama na 8 a Championship. A 1980 Simon ya koma CART kuma ya ci gaba da samun nasara a cikin shekarun 1980 yayin da yake kasancewa mai gasa. Ya shiga mafi kyawun lokacinsa na CART a 1987 lokacin da ya fara farawa 11 kuma ya shiga cikin manyan goma da suka hada da na 6 a Indy 500, wanda ya isa ya zama na 20 a gasar zakarun CART. Wani lokaci a shekarar 1988 inda Simon ya shiga matsayi na 9 a Indy 500 shi ne na karshe a matsayin direba.