I'm looking to switch from the 4.56 gears I have in my Moser Dana 60 to a 4.30 ... I think .
It's a street/strip 76 Dart Sport weighing 3200, 455cid small blk, 727 with trans brake, 30" slick and has run a best of 9.76 @ 137 open exhaust ... shift light is at 7200 so shift probably occurs at 7400 and the light is on at the 1000' mark so I'm crossing the stripe at 7400+

Peak HP/TQ throught the mufflers from the chassis Dyno was 585 at 6750 and then drops to 573 and holds there till 7200 (end of run) Peak TQ was 482 at 6350

Am I over geared ??? I'm thinking a 4.30 would bring it down to the 7000 ish mark and I might pick up some et/mph
Any thoughts ?