All current SRT-8 products use Chrysler's 6.1L HEMI V8, so we would expect the same powerplant for the Challenger SRT-8 producing 425 horsepower and 420 ft-lbs. of torque. However, considering how many high-powered variants of the Mustang are offered, and that Chevy will certainly offer a comparably high-powered version of the Camaro, we expect the SRT-8 to break rank with its siblings and have considerably more power than we're used to seeing in an SRT-8 product. In fact, we may reasonably expect all SRT-8 models to get an commensurate bump in power after the Challenger SRT-8 debuts in late 2009, especially with some like the Dodge Charger, Magnum and Chrysler 300 switching from the current LX platform to a new one code named LY.
BTW - Less than 159 days remain until the production Chrysler Challenger debuts at the Chicago Auto Show next February (check the countdown clock).