Hemi 5.7 Exhaust System
1. Diablo sport tuner...hands down the best.
2. 2 1/2 inch with an x-pipe for best power, or use an h-pipe, whatever suits your cars fitment.
3. Headers will give more power, and there shouldn't be any clearence issues with the front suspension you plan on using, but don't quote me on this one.
4. Not sure on the '10 models.