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isn't shown or measured on dyno charts. Dynos typically start their measurement at positive manifold pressure (typically around 2 pounds). What it doesn't show is the real world time it takes the system to go from vacuum (where the throttle is mashed) to that 2ish pounds of manifold pressure. There seems to be a mis-perception that if the car is making more power/torque at an earlier RPM on the dyno graph, then the transient response is improved. Case in point: if two Zs are side by side, one with larger turbos (sport 700s, GTX 2860s, etc) and one with smaller turbos (stock, sport 500s, 530s, etc), and similar supporting mods, at the same RPM, the smaller turbo car is going to respond quicker (have better transient response) than the larger turboed car; even though the dyno on the larger turboed car will have more power on the dyno thru most of it's powerband. I also think there is a mis-perception that cams, larger intercooler piping, and some other "breather mods" improve transient response. Again, because of a dyno that makes more power at lower RPM, but doesn't measure actual transient TIME (the clock time it takes the turbos to go from a vacuum condition until they are lighting off). They certainly make more power and increase area under the curve, but some "breather mods" add lag. I've wondered why our cars have added so much more power over the years but haven't been able to perform better in the 1/4 mile. They go way faster (MPH) than, 15ish years ago, but the ETs haven't gone down commensurately. I think this is because of the lowered off throttle torque/higher transient response/increased lag. The result is higher 60' times, an increase of time to go back into boost between shifts (more lag), and a high ET to MPH. I'm just using the drag racing scenario to illustrate the effects some modifications have on transient boost. Sorry for the novel.
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