RE: 7.0 Hemi?
I work for a dodge chrysler jeep dealer. Ive heard a couple different things. One, is that the R/T challenger will feature the 6.1L engine, instead of the normal 5.7L hemi. Then the SRT challenger would eventually feature the 6.4L hemi, Producing 500+ hp. While that would be nice, I dont think they will do that.
As far as the 7.0L Hemi.... John Hennesy's tuning company makes a kit for the srt8 jeep grand cherokee that bores the regular 6.1L hemi out to 7.0L. Ive never seen one race but if you do a search in youtube for a 7.0L grand cherokee, you will find a vid of the engine running and reving. Sounds nasty. I think the name of the mod is the Hennesy 600 or 650. I think that dodge would have trouble putting such a big engine stock in a challenger, as they are already having problems matching a 6.1L hemi to a manual transmission.