Based on what my tuner has told me and from my data logging on my computer the surging people are experiencing near 2k rpm is the engine running very lean for about a second and picks back up also when WOT the air fuel was running extremely rich. For new people to boost a desired number cruising is 14.7 for air fuel anything above is lean and below that number is rich. My tuner told me that ideal air fuel when WOT full boost should be around 11.1 i was running 8.3 and was losing gas out the tail pipe and lost power running that rich. He tuned it and it runs just like a normal factory truck. Ripp did a well job dialing a in box tune so you can drive it all day everyday but i suggest just getting it dialed in spend the money know your engine is running proper i beleive no truck is the same and will run slightly different depending on conditions