I found this tidbit of information in a wikipedia article about Hemi engines:
"On Aug. 17, 2007, a rumor surfaced that the 2008/2009 Challenger SRT will, in fact, be powered by a 7.0L hemi engine - marking the return not only of the Challenger marquee, but also of a 426 cubic inch displacement engine. The engine reportedly will be based (loosely based) on the current hemi engines, but will feature four valves per cylinder with dual-independent variable cam timing. Reportedly, this step was needed to best the Chevrolet LS7 engine, which is slated for the 2009 Camaro redux. Performance figures for the 7.0L hemi have not been disclosed yet."
To read the full article see:
http://en.wikipedia.org/wiki/Chrysler_Hemi_engine