Originally Posted by dennismonsewicz
With some of the items you mentioned (addons for the vehicle), how much improvement can I expect?
Best case, you'll be looking at maybe
1-2 mpg increase, if you're really luck you might get 3 mpg once in awhile.
There isn't really a hell of a lot that you can do to increase the fuel mileage of the HEMI, other than slow down and do the "Driving Miss Daisy" thing.
I've tried really hard, and the best that I've ever seen around town is about 15 mpg, and that was doing really slow starts, and trying to keep the revs under 3000 rpms. With my wife driving on a 600+ mile trip we did see 21 mpg on the interstate, though the best I've done personally is about 19.6.
The HEMI likes to drink the fuel, and there is very little that can be done, except to feed the beast.