Jeep’s 470-hp_Grand Cherokee SRT8 is pretty bad-___ as it sits, all pumped-out bodywork, crushing curb weight, and V-8 rumble, but Chrysler’s Mopar parts division may be working up some performance pieces for the big beast. At Mopar’s SEMA stand, the Grand Cherokee SRT8 that had competed in this year’s One Lap of America event was [.]