I have tested several different rear gear ratios in my old pump gas Duster, 3:73, 3:91,4:10 and 4:30 in the 8 3/4 housing using 742 carriers for all of those ratios, I saw no noticeable change in the time slips in the 1/8 mile and 1/4 mile. That was with a six pack intake and magic carbs confused shruggy That car weighed 3450 lbs. with me in it with a full tank of gas in the stock gas tank
That car ran a best of 9.99 at 134.+ MPH corked up using Oregon 92 octane pump swill with the air cleaner on through the full 3.0 exhaust system exiting at the rear bumper work
My last bracket car weighed 2850 lbs. with me in it and it would run 5.50 in the 1/8 mile at 125.MPH, 8.86 ET at 150. MPH in the 1/4 mile on E85 with a very similar motor as the Duster with higher compression running on E85. That car was a 1970 Cuda all out full chrome moly chassis with a glide and several different converters in it, stalled at 5600 RPM against the trans brake at WOT and shifted between 7000 RPM at first and later shifted it at 7300 RPM which picked the MPH only up in the 1/4 mile by 2.0 MPH shock shruggy
That car had 4.56 gears in the Dana 60 with a four link coil over rear suspension that worked very well,1.23 60 fts. boogie up 15x33x15 inch Goodyear slicks on 15 inch wide rear rims up

Last edited by Cab_Burge; 12/16/23 04:21 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)