9 3 4 – 1 9 5 3 . ▁K line ▁is ▁thought ▁to ▁have ▁made ▁an ▁inform al ▁" G ent le men , ▁start ▁your ▁mot ors !" ▁command ▁as ▁early ▁as ▁ 1 9 4 8 ▁to ▁accomp any ▁the ▁bomb . ▁The ▁first ▁documented ▁case ▁was ▁in ▁ 1 9 5 0 , ▁and ▁that ▁was ▁rec ited ▁by ▁pro l ific ▁public ▁address ▁announ cer ▁John ▁Francis ▁" I r ish " ▁Hor an . ▁K line ▁was ▁again ▁reported ▁as ▁saying ▁it ▁in ▁ 1 9 5 1 , ▁( though ▁some ▁report ▁it ▁was ▁Hor an ) ▁Either ▁K line ▁or ▁Hor an ▁said ▁it ▁again ▁in ▁ 1 9 5 2 . ▁It ▁was ▁around ▁that ▁time ▁the ▁command ▁was ▁changed ▁from ▁"... mot ors !" ▁to ▁"... eng ines !" ▁The ▁participants ▁and ▁officials ▁al ike , ▁preferred ▁the ▁more ▁technical ▁term ▁" eng ines " ▁to ▁describe ▁their ▁machines . ▁Sid ▁Collins ▁stated ▁that ▁chief ▁ste ward ▁Har lan ▁F eng ler ▁explained ▁to ▁him ▁" there ▁are ▁no ▁mot ors ▁in ▁the ▁race , ▁just ▁engines ." ▁ ▁Wil bur ▁Shaw , ▁president ▁of ▁the ▁Speed way ▁in ▁ 1 9 4 6 – 1 9 5 4 , ▁was ▁once ▁believed ▁to ▁be ▁the ▁person ▁who ▁co ined ▁the ▁phrase , ▁and ▁it ▁was ▁err one ously ▁claimed ▁in ▁his ▁aut obi ography ▁that ▁he ▁rec ited ▁it ▁in ▁all ▁the ▁post - World ▁War ▁II ▁years ▁until ▁his ▁death .