brady, i've got a lot of cam in mine and it's just lugging at (legal) hiway speeds.
same setup with a 400 turbo (yeah, i've had to play with driveshafts) got better milage and was more fun to drive (with the 3.25 gears).
you'll need at least a 3.73 gear to be livable with a carb motor.
just like everybdy else has been telling ya, it depends on YOUR combination.
ain't gonna matter to me much anyway, it's goining in for a cage this winter and i'm gonna fit it for a 4 or 5 speed manual trans and do some draggin'