Actually Jack I have tried that by making passes and shifting at 5500 rpm, and I actually lost a little time. My peak horsepower is at 5600 rpm, so I try to go slightly past that..ie 6000. I made some test runs where I shifted at 6000 and then shifted at 5500 and after comparing the different increments ( 60' to 330', 330' to 1/8, 1/8 to 1000' and 1000' to 1/4 mile) I found that the only increment quicker with a short shift at 5500 was from 1/8 to 1000'. Therefore I actually shift from 1st to 2nd and 2nd to 3rd at 6000 rpm and I short shift 3rd to 4th at 5600 rpm and that has given the best results. Each truck is different and maybe because of the ported intake and my equal length true dual x-pipe exhaust my engine likes a little more rpm......it works for me........but thanks for the tip, I appreciate you looking out for this old fart....and we will stick together!