i disagree with that comletely, at least on a dyno you have same conditions and you dont have issues pertaining to traction, weight, weather, etc....., on a dyno, you dont have to worry about that affecting you differently each time, it might be hot or something in the dyno room, but wind isnt gonna be blowing you to the left and your not gonna worry about spinning tires of the launch and what not, you can get a better result "test wise" on a dyno than you could on the racetrack, cause what happens when you spin tires in 2nd and the next run you dont and your time is 2 tenths slower than usual and you end doing it back and forth and never go faster than what the car used to run, youll end up blaming it on the intake instead of your driving and youll give it false reviews, thats not the intakes fault, my opinon is the best way to prove hp is on the dyno doing power pulls and monitoring the vitals of your car and making sure there equal on each test run.........like making sure the car was at less than 100 degrees or whatever on the water temp guage before attempting a dyno pull, and that the 2nd pull you do has fresh plugs and what not.......