So the T-5 will drop it to 1950 rpm. Where does you engine produce it's best efficiency? The cam in my 270 loves 3,000 and I have to pay attention to keep it from going there. With my tires, 3.55 gears and T-5 3,000 is 90 mph. 2,000 rpm is 60 mph but it doesn't pull well there. So 2,200-2,500 IS 70-75 mph and I got right at 17 mpg. I'm sure ai could tune and get 20. With 28" tires it pulls better but goes slower. It sounds like you are getting in there, in that range of efficiency. I think tire size is the last adjustment.
"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
