Feel pretty confident with the results and friend is pretty happy. I still feel as thought the bottom end take off from a stand still could be stronger. My 5.3 05 tahoe accelerates alot better to the 1-2 shift that this truck does. I havent driven enough 6.0s to get a good comparison. My friend tows a race car and doesnt always run 93 octane so i stayed a little conservative on the timing and what not. please look over and give some insight.