Brentil's right...the turbocharger system in your car is very adaptable to changing weather and atmospheric conditions. I'd make a guess that the weather in your region has heated up as of late, so your engine is raising boost pressure to compensate for the lower air density.
It's a beautiful thing...previous turbo cars weren't so well endowed, and would just suffer in warm weather!
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Bill Hahn Jr., Hahn RaceCraft, Inc.
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