Nyorai kupfuurira kweiyi ndima - Muna 1979, huwandu hukuru hwekufambira mberi hwakaitwa mu aerodynamics uye kupokana neLotus, Forghieri akaziva kuti aifanira kutevera kutungamira kwavo uye kugadzira mota ine simba repasi ra1979. 312T4, yakatangwa paSouth African Grand Prix ya1979
yakanga yakavakirwa zvikuru pa312T3. Mavambo ayo akaisa zvinorambidza pane aerodynamic dhizaini sezvo iyo T dzakateedzana yakanga isina kumbobvira yakagadzirirwa nepfungwa yepasi. The 312T4 monocoque rakagadzirirwa kuva sezvo yakamanikana sezvinobvira, kushandisa migumisiro pasi, asi ichi chakanga chakaganhurirwa upamhi flat 12 injini.