More oxygen in cold air and it is more dense, thus slightly more boost (quicker) and better performance. When its 30F or less outside my car can rip some pavement, I love the performance in the cold! Boost builds quicker...more oxygen = more complete burn in the cylinders = more power

I noticed it today, I was able to accelerate VERY briskly, had lots of torque feel, it is presently about 25F out.

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