I am right below Nashville and in the county not city. I have 4 interstates that I typically have to get on to go anywhere that has distance. They are I24, I65, I840 and I40 and all are 70mph. My commute to the office is about 5 miles on a 55 mph stretch. Not a whole lot of in town and even at that it is typically 40-45 mph. 3rd and 4th gear will be the most used.
Torque is absolute something I have considered. 2500rpm is what I based the calcs off. You align with what I have come up with per the Tremec Gear calculator.
3.73 rear end gear. 30" tire
1st gear 4.03@2500 rpm= 15MPH
2nd gear 2.37@2500 rpm= 25MPH
3rd gear 1.49@2500 rpm= 40MPH
4th gear 1.00@2500 rpm= 59MPH
5th gear .76@2500 rpm=78MPH
You are right a 28" tire doesn't change a great deal. However I was considering a 18' wheel( Dad had 15" with a 225/70 on there) in which a 30" will look good. If I go to a 16" I may end up with a 28" or 29" depending on the aspect ratio. I will not go miss match, so if 30" doesn't work on the front I will go smaller.
