I had a problem on Monday where my car had an unintended acceleration hiccup. Still not sure what the cause of it was but I'm blaming the ETM for now.
Anyway, Tuesday I had a buddy with an OBDII scanner come for a ride with me. Aside from monitoring some mildly erratic behavior from the TPS that could be caused by the feedback loop in the system or a wearing potentiometer in the ETM, we noticed some cool boost pressures.
First and second gear are a crap shoot because the torque converter is unlocked in these gears, acting as a torque multiplier, putting less load on the motor thus creating less boost, roughly 1-6psi. I noticed a vacuum of 0.1-1psi in some instances under medium throttle. Once the torque converter locked in third we got some interesting readings...
TC locked, low-end, WOT @ 1500-3000RPM, multiple run observed averages;
Third ~20.5 psi
Fourth ~17.8 psi
Fifth ~15.9 psi
Above 3000RPM it dropped about 1 psi until the torque band fell off after 4500RPM and once the power curve passed the torque curve around 5400RPM there was about 3-5psi less.
I thought the information may be useful to some since I couldn't find anything stating real world boost pressures. After being totally surprised with that bit of information. I've been trying to find another turbo motor on the market that makes more boost from the factory and so far there's only a Bugatti Veyron SS which pushes about 21.8psi stock.
I'd imagine the Polestar tune for this 2.5T (B5254T2) motor changes when the torque converter locks to run higher boost pressures sooner.
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