▁changes ▁under ▁the ▁h ood ▁were ▁major . ▁The ▁compression ▁ratio ▁was ▁raised ▁from ▁ 6 . 1 5 : 1 ▁to ▁ 7 . 0 : 1 , ▁the ▁" t ur bul ator " ▁p ist ons ▁were ▁red es igned , ▁smaller ▁spark ▁pl ugs ▁were ▁subst it uted ▁for ▁the ▁previous ▁type ▁and ▁“ Comp ound ▁Car b ure tion ” ▁was ▁introduced , ▁as ▁it ▁was ▁on ▁all ▁Bu icks ▁except ▁for ▁the ▁Special . ▁Comp ound ▁Car b ure tion ▁was ▁the ▁for er un ner ▁of ▁the ▁modern ▁four - bar rel ▁car b ure tor , ▁and ▁consisted ▁of ▁tw in ▁two - bar rel ▁car b ure t ors . ▁One ▁unit ▁operated ▁all ▁of ▁the ▁time , ▁while ▁the ▁other ▁operated ▁only ▁under ▁hard ▁acceleration . ▁The ▁new ▁engine ▁delivered ▁ 1 2 5 ▁horse power . ▁All ▁cars ▁available ▁with ▁a ▁choice ▁of ▁ax le ▁r ati os ▁and ▁with ▁two - t one ▁color ▁combinations ▁with ▁ 1 9 ▁se lections ▁at ▁no ▁extra ▁charge . ▁A ▁new ▁feature ▁was ▁a ▁two - way ▁h ood ▁that ▁could ▁be ▁opened ▁from ▁either ▁side . ▁The ▁ 4 - door ▁convert ible ▁and ▁the ▁Est ate ▁w agon ▁were ▁gone ▁but ▁a ▁new ▁one ▁year ▁only ▁body ▁style ▁was ▁a ▁ 3 - pass enger ▁ 2 - door ▁Business ▁Coupe ▁which ▁sold ▁ 2 4 4 9 ▁units . ▁Over all ▁sales ▁fell ▁to ▁ 9 2 , 0 6 7