▁For ▁a ▁brief ▁time ▁in ▁the ▁early ▁ 1 9 8 0 s , ▁some ▁of ▁the ▁D FX ▁engines ▁were ▁bad ged ▁as ▁F ords . ▁The ▁D FX ▁power ed ▁ 8 1 ▁consecutive ▁Ind y ▁car ▁vict ories ▁from ▁ 1 9 8 1 ▁to ▁ 1 9 8 6 , ▁and ▁ 1 5 3 ▁vict ories ▁total . ▁By ▁the ▁time ▁it ▁was ▁replaced , ▁the ▁D FX ▁was ▁developing ▁over ▁. ▁ ▁D FS ▁In ▁ 1 9 8 6 ▁G M ▁fin anced ▁the ▁British ▁Il mor ▁firm ▁to ▁build ▁a ▁compet itor ▁to ▁the ▁D FX ▁in ▁American ▁Ind y ▁car ▁racing . ▁Mario ▁Il li en ' s ▁Il mor - Che v ro let ▁Ind y ▁V - 8 , ▁which ▁ow ed ▁not ▁a ▁little ▁to ▁the ▁D F Y ▁of ▁five ▁years ▁earlier , ▁quickly ▁took ▁over ▁domin ance ▁of ▁the ▁sport . ▁ ▁Ford ▁respond ed ▁by ▁commission ing ▁Cos worth ▁to ▁red es ign ▁the ▁D FX ▁to ▁include ▁a ▁number ▁of ▁D FR ▁improvements . ▁In ▁ 1 9 8 9 , ▁they ▁introduced ▁an ▁updated ▁" short ▁stroke " ▁version ▁of ▁the ▁Ind y ▁car ▁engine ▁which ▁would ▁be ▁referred ▁to ▁as ▁the ▁" DF S " ▁(" S " ▁for ▁short ▁stroke ). , ▁and ▁the ▁Nik as il ▁Al umin ium ▁lin ers , ▁adopted ▁on ▁D F Y ▁in ▁ 1 9 8 3 . ▁The ▁engine ▁was ▁field ed ▁by ▁two ▁teams ▁in