According to this Popular Mechanics road test the 5.7 Challenger could only muster a 14.4 quarter mile. And that was with a 6 speed and 3.92 gears. From what I read in the article it looks like the Challengers are just too darn heavy! Over 500 Lbs. heavier that a similar equipped Mustang GT.
http://www.popularmechanics.com/blogs/automotive_news/4309423.html#comments