when was there a change ?
 

looking at a 2007 jeep it has the hemi .. but im curius if the hemi was upgraded in power in 2008 models ?

Besides small things and the multiple cylinder displacement the only big change in hard parts is the intake but that was only on truck applications until you get up to 09 then they were bumped up about 60 ponies

FYI its not really a hemi its a pentroof design. But its as close as they can get and still keep the EPA and CARB people happy