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Regarding measured/logged boost spike in the 3000-4000rpm area: This is largely caused by two things:
1) a delay in throttle opening (if you log TPS, you'll see it doesn't "snap" open immediately). Instead, the opening is more gradual. This means that for a fraction of a second, the boost pressure in the intercooler tube (where boost is measured) is 1-2psi higher than it is in the intake manifold (what is actually seen by the engine).
2) Dramatic valve/cam timing phase shift. You can see this on the dyno as well (even in a stock car). There is a bump in the torque curve right around 4000rpm. Prior to this point, boost is higher. After this valve timing change, boost drops due to increased pumping/VE efficiency.
...Just wrapping up final docs and map tweaks on v2.0.2.
Shiv
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