This is leaning into racing dynos. A good example is the 376 Victor headed engine w/the modified W2 Holley Strip Dominator. There was a big difference from the builders dyno (770) to the competition dyno. (737)
Between engine dyno’d and flow benches, it can be a cluster frak in a nutshell. I take them all with a gain of salt and just simple try and see how things are effected with changes.