Yeah without a blower or S/C you can't get these below 3.3-3.5 0-60mph, based on my years of watching the SRT's (WK1 06-present) and their progress with the Engine/ECU/Tranny. Still quite impressive what they have done in s 5k lb SUV
My PB is 3.9 seconds. 3am, 42 degrees out, minimal moisture, Sport/Track mode, NO launch control
...was about 2/3rds warmed up. It was my first pull that morning. I quit on the spot haha. These beasts really like the cold weather, and with good tires they almost always hook on good roads with nice conditions.
Either you were going downhill, or like Nitemare said the tires spun and tricked it into a faster time...