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lag = physical time it takes for a turbo to spool when its in its operating rpm band, what you guys are referring to is actually boost threshold (what rpm the turbo spools at)

i remember reading about the sts kit ages ago, the designer/engineer or some shit said that becuase there was the same mass in exhaust gas, it could spool a turbo all the same, just with a smaller rear to compensate for the lower volume (due to heat loss), or something along those lines anyway.

ummm, actually no. we aren't talking about what the threshold is. we are talking about response. as in how long after you plant your foot the turbo spools up and starts actually pressurising the intake. the length of the piping doesn't really affect the threshold at all as that is simply determined by the amount of exhaust gas and size of the rear housing and turbine wheel, not the length of the piping (although this will play a very small part, because as you said, the longer the exhaust the cooler the gases will be and the less volume they have).

It also wouldn't be hard for Porsche to get one of those aftermarket ECU tuning tools to drop the boost or pull out some timing, let alone something like inserting restrictors into the intake or any other multitude of invisible mods (not that anyone saw the car Porsche used as they didn't publish a video).

and whilst that is also possible, i think that porsche would've initally run it at stock setup to see what it could actually do. so they would've given the car to their driver to do a few laps before they even thought about detuning it. no point detuning it if their driver can't match the times in stock form.

so to be honest, unless a third party buys a new car from the showroom floor of each brand and takes them there, calls the press in and has multiple drivers start doing laps, you won't know for sure which is quicker. because drivers are another variable. each car is going to suit different drivers slightly better.

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ummm, actually no. we aren't talking about what the threshold is. we are talking about response. as in how long after you plant your foot the turbo spools up and starts actually pressurising the intake. the length of the piping doesn't really affect the threshold at all as that is simply determined by the amount of exhaust gas and size of the rear housing and turbine wheel, not the length of the piping (although this will play a very small part, because as you said, the longer the exhaust the cooler the gases will be and the less volume they have).

sorry, wasnt directed at you specifically.

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