eh guys some people just don't want a manual, or even to learn. nothing wrong with that
5.0 might not be all that fast but it's a beast (had one in my 2000 mercury mountaineer 4x4)
but 13mpg got old
the best answer is that you're not going to get much faster, period. Your choice is to turbo, or swap but other than that there are no bolt on devices that will magically make the D series motor fast. I have a header, intake, exhaust, AND 5 speed and its still slow as poo. but it's as fast as it can be without some serious modding because these cars were built for economy NOT speed. People build them for speed, by pretty much changing everything about them
If you're looking for a fast car I recommend either turbo, swap or sell and buy something faster. Thats really you're only options other than just live with have a slow car that gets good gas mileage