▁tax ▁bill . ▁The ▁B 4 ▁mon iker ▁also ▁applied ▁to ▁naturally ▁asp ir ated ▁models , ▁such ▁as ▁the ▁ 2 . 0 L ▁T S - R . ▁ ▁Australia ▁models ▁( called ▁B 4 ) ▁were ▁det un ed ▁to ▁run ▁on ▁lower ▁oct ane ▁( 9 8 ▁R ON ) ▁fuel ▁and ▁were ▁r ated ▁ ▁for ▁the ▁manual ▁and ▁ ▁for ▁the ▁automatic ▁models . ▁This ▁results ▁in ▁a ▁ 0 – 6 0   m ph ▁time ▁of ▁ 5 . 6 ▁seconds ▁for ▁the ▁manual ▁and ▁ 6 . 6 ▁seconds ▁for ▁the ▁automatic . ▁ ▁A ▁B 4 ▁T S - R ▁model ▁was ▁equ ipped ▁with ▁a ▁less ▁powerful , ▁naturally ▁asp ir ated ▁ 2 . 0 ▁L ▁DO HC ▁A VC S ▁engine , ▁but ▁shared ▁many ▁of ▁the ▁body ▁and ▁susp ension ▁components ▁of ▁the ▁more ▁powerful ▁R SK . ▁ ▁In ▁ 2 0 0 1 , ▁a ▁B 4 ▁R S 2 5 ▁model ▁was ▁introduced ▁with ▁a ▁naturally ▁asp ir ated ▁ 2 . 5 ▁L ▁DO HC ▁engine . ▁ ▁In ▁ 2 0 0 2 , ▁the ▁B 4 ▁R S 3 0 ▁was ▁introduced ▁with ▁a ▁naturally ▁asp ir ated ▁ 3 . 0 ▁L ▁E Z 3 0 ▁DO HC ▁flat - six ▁engine . ▁ ▁B 4 ▁Engine ▁Str ucture ▁ ▁The ▁B 4 ▁is ▁power ed ▁by ▁a ▁' phase ▁ 2 ' ▁all - al loy ▁DO HC , ▁ 1