inder . ▁Second ly ▁the ▁cars ▁t anks ▁- ▁radi ator , ▁oil ▁and ▁pet rol ▁- ▁had ▁fill er ▁caps ▁that ▁did ▁not ▁uns cre w ▁but ▁were ▁easily ▁removed ▁with ▁one ▁stroke ▁of ▁a ▁lever . ▁This ▁saved ▁time ▁during ▁stops . ▁ ▁W . O . ▁believed ▁that ▁the ▁super char ger ▁cor rupted ▁ ▁his ▁design . ▁The ▁huge ▁Ro ots - type ▁super char ger , ▁known ▁in ▁racing ▁circles ▁as ▁a ▁blow er , ▁was ▁added ▁in ▁front ▁of ▁the ▁radi ator ▁and ▁driven ▁straight ▁from ▁the ▁c rank sh aft . ▁This ▁gave ▁the ▁B lower ▁Bent ley ▁a ▁unique ▁and ▁easily ▁recogn is able ▁profile , ▁and ▁ex ac erb ated ▁its ▁under ste er . ▁The ▁c rank sh aft , ▁p ist ons ▁and ▁lub ric ation ▁system ▁were ▁also ▁special ▁to ▁the ▁B lower ▁engine . ▁ ▁A ▁guard ▁protected ▁the ▁two ▁car b ure t ters ▁located ▁at ▁the ▁compress or ▁int ake . ▁Similar ▁protection ▁was ▁used ▁( both ▁in ▁the ▁ 4 ½ ▁Lit re ▁and ▁the ▁B lower ) ▁for ▁the ▁fuel ▁tank ▁at ▁the ▁rear , ▁because ▁a ▁flying ▁stone ▁pun ct ured ▁the ▁ 3 ▁Lit re ▁of ▁Frank ▁Clement ▁and ▁John ▁D uff ▁during ▁the ▁first ▁ 2 4 ▁H ours ▁of ▁Le ▁Mans , ▁possibly ▁dep riv ing ▁them ▁of ▁victory . ▁ ▁The ▁mechanical ▁add itions ▁and ▁modifications ▁took ▁the ▁power ▁of ▁the ▁base ▁car ▁from : ▁Un b low n : ▁tour