The last SB 4 speed Duster I drove had 5.57 rea gears with a 3.09 first gear in the tranny using 13x30x15 inch slicks, you where real busy in that rascal the first 300 ft. boogie up
That car weighed right at 3200 Lbs. with me in it and only ran low 11.s whiney shruggy

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)