Well your right about the numbers changing with an automatic and overdrive , I have an 09 JK with 513's with 37" tires and at 70 mph Im cruising at 2400 2500 rpm with plenty of power , but when I turn off the overdrive it sky rockets to 3200 3300 !! Thank god for that over drive !! And in low gear (4-1 Rubicon transfer) I have more power than I need !!
Tear It Up - Fix It - And Do It Again