▁Ro ▁ 8 0 , ▁which ▁had ▁a ▁ 1 1 5 - hor se power ▁engine ▁with ▁two ▁rot ors . ▁ ▁It ▁was ▁the ▁first ▁German ▁car ▁selected ▁as ▁" Car ▁of ▁the ▁Year " ▁in ▁ 1 9 6 8 . ▁ ▁In ▁Japan , ▁the ▁manufact urer ▁Maz da ▁solved ▁the ▁engine ' s ▁ch atter ▁marks ▁problem , ▁by ▁reducing ▁a pe x ▁se als ' ▁weight , ▁that ▁made ▁it ▁entering ▁reson ating ▁v ibr ations . ▁The ▁engine ▁has ▁been ▁successfully ▁used ▁by ▁Maz da ▁in ▁several ▁gener ations ▁of ▁their ▁R X - series ▁of ▁coup és ▁and ▁sed ans , ▁including ▁the ▁Maz da ▁Cos mo , ▁R 1 0 0 , ▁the ▁R X - 7 ▁and ▁more ▁recently ▁the ▁R X - 8 . ▁Mer cedes - B enz ▁completed ▁its ▁C 1 1 1 ▁experimental ▁model ▁in ▁ 1 9 6 9 ▁with ▁ 3 - rot or ▁W ank el ▁engine . ▁In ▁ 1 9 7 0 , ▁the ▁next ▁model ▁had ▁a ▁ 4 - rot or ▁W ank el ▁engine ▁and ▁could ▁reach ▁top ▁speed ▁ 2 9 0   km / h ▁but ▁never ▁reached ▁serial ▁production . ▁ ▁W ank el ▁became ▁a ▁success ▁in ▁business ▁by ▁se cur ing ▁license ▁agre ements ▁around ▁the ▁world . ▁By ▁ 1 9 5 8 ▁W ank el ▁and ▁partners ▁had ▁founded ▁the ▁" W ank el ▁GmbH " ▁company , ▁providing ▁W ank el ▁with ▁a