4 days on a full tank is pretty good . No way would you get 500 miles on a tank . Unless your pushing the car I avg 25-28 city and rufly 30-32 on hw . This was on summer gas . Winter gas you will get worse millage this was on my 11 2.5i ..
They make a supercharger kit for the 2.5i raptor there a company out of Australia found a shop in nh that can get them .was about to pull the plug on one but have head gaske leak .. so got to take care that first..