Assuming that your gear set is pretty high, I suggest that you consider a lower gear like a 3.73 and then change the transmission out to an overdrive such as a 700R4 or 200 4R. Lot of good info on those here: http://www.bowtieoverdrives.com/index.shtml. Whether you buy from them or not.

By making these changes you will notice a huge improvement in the seat of the pants feel you get because the OD transmissions have a much lower first gear. That combined with the lower rear end gears will give you the feel you want. Then with the Overdrive high gear, you will still have the low RPM cruise for economy and reduced strain on your motor. If you have to do one before the other, I would change the transmission first, then the gears.

They have charts on the Bowtie Overdrive page that will help you calculate what your gear ratio is based on tire diameter, speed and RPM so you won't need to pull you rear end apart to figure your geaar ratio. You will need a tach to do that.

Pat