guys as a person who has followed LX cars for years now this is a recurring and main problem with LX cars. The halfshafts are the first thing you should replace when you start modding your engine. Tons of chargers srt8s and 300s break their halfshafts the first or second time they go to the track with some new bolt ons. Go to youtube and search for broken srt 8 halfshafts, you will see videos of guys warmin up the tires right before they get ready to run and once the tires stop spinning and the car moves foward with the power the halfshafts snaps. This is the weakest link in all LX cars period...including the challenger. Do yourself a favor and get a 1000hp halfshaft before doing any extensive modding to your car.
Alot of challenger owners don't know this because this is their first lx xar or they just dont follow the charger forums ect. But trust me, I am one who has followed the LX forums and this is a must for anyone trying to push 400+ to the wheels.

just my 2 cents