I have the same issue, too, even when I was N/A. Everyone tells me it's a tuning issue. But this hesitation and lack of power you see is the throttle not opening up as much even when you're flooring it. I can tell because car barely hits boost in 1st or 2nd with my foot planted at 4k RPM. Like you said, power surges at 2k RPM. Try blipping the throttle past 2k RPM, and then get in 1st like usual. Or get the car going above 2k RPM, and the engine will scream. Someone mentioned throttle restrictor.
Whatever it is especially for a stock car, this lag has been discussed since 2009. At first we thought it was throttle by wire lag, but now it seems like the throttles are not opening up.
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