ORIGINAL: Mikesan
I also suspect that the 425 HP rating will be under-rated. Wasn't it in the SRT-8 300's?
The 6.1L SRT8 425HP engine is in the Charger SRT8, the Magnum SRT8, the Jeep Cherokee SRT8, and the 300C SRT8.
There are several programmers/chips available to flash the BIOS for both of the HEMI engines. My friends who've used them recommend the Diablo over SuperChips for the HEMIs.