hey man, You have 3 choices:
1) The power control module from jet performance give extra hp (15hp) parts number 680036
2)You have asechips they have a chip for this engine :www.asechips.com
3) from chrysler you can have another computer whit high speed rate tires (22560VR16) No hp up, but the speed limiter is 139mph mopar part:0501267AA
I Trie the jet module ( you cant see the module on weeb site you must call) and I notice a little augmentation of hp but is not like a real chip. Maybe you must trie asechip but you must send the Pcm.