Right then, a quick log I took today especially for you guys
I'm slightly nervous about posting it, as it may well create as many questions as answers, but here goes.
This is an aggressive throttle blip from idle with the car fully warm and in neutral. Its a large capacity V engine with a supercharger, and using the latest generation DENSO EMS with full torque based control. The channels are logged at a 1ms rate, which in the case of the throttle and pedal signals is actually faster than they are being processed (the raw input is seen quite quickly but the % converted variable that I chose to log is updated every 8ms, hence the steps)
The important bits.
This was about as fast as I could stamp the pedal. Closed to fully open takes 70ms
The time to get from 30kPa to atmospheric pressure is around 200ms, but....
There is a significant delay (around 90ms) before anything happens in the manifold
This means that the fastest rate of change of MAP is actually around 1kpa/ms
The engine speed has barely risen from idle speed before the MAP has reached atmospheric.
Now the slightly more tricky bits....
The throttle plate initially opens to 20% very quickly, and then holds at a level. In fact, you can see that this doesn't have a significant impact on the MAP at first. This is your introduction to the concept of 'effective wide open throttle', which means that at low airflows you only need to open the throttle a small amount for it to stop being a restriction. In this case 20% is effective WOT, and anything over this makes no difference. As revs and MAP begin to rise, so the throttle is required to open more in order to avoid choking the flow, which you can see it doing. The EMS does this in order to minimise response time to keep the best control - i.e. if the pedal is released again the throttle will instantly start to close and be a restriction, rather than having a 20 or 30ms delay. This is important for things like auto box gear shifts or traction control events where torque has to be reduced and reinstated very quickly and accurately to be 'seamless'.
Once things get moving and the engine speed starts to rise you can see the charger starts doing its stuff and boost increases past atmospheric. But the really difficult bit (for transien fuel comp) is past by now, so we don't really care (hence I've cropped the log).
Lastly you can see the MAP curve, and how it takes a bit to get going (inertia) and slows down as it approaches atmospheric (less delta P). However this is all a bit clouded by the throttle moving and the charger being attached, so this is by no means the same shape of curve for every engine. Upstream pipework, throttle size, plenum and runer volumes etc will all play their part in the particular shape of this curve for your engine.
So if you perform that same test with PW and lambda being logged, having already measured the lambda transport delay so that you can offset it correctly, you can look at calibrating transient fuelling in the most logical way
Hope thats useful