My street tires are 305/50R20 Terra Grapplers
they are 12.2" wide by 32.2" high and on mystock 20's weigh in at over 90lbs ea.
I currently run 14.4's on them at the track
..and thats at 2500'+ DA, would be high 13's at sea level.
I'll probably turn them at 2300+ rpm on the highway with 4.56's, but that wouldn't be very often.
My truck is primarily my city commuter/weekend warrior and wont see 5th gear very often.
I run a 93 octane tune all year round, never less than 94 octane fuel,
my throttle boost and shift points on my Diablo Trinity are maxed out.
Fuel economy has never been a concern, go fast or go home.
Although I've never re-geared a truck for the track,
I have done many Jeeps with 4.56's and ARB air lockers front and rear,
so I do know and appreciate the performance benefits of a gear swap.
I was a Jeep Jamboree Trailguide for almost 10 years
my last ride....built by myslef from the ground up except for the axles, I leave that to the pro's