I could be off a little but I have heard this to be a good way to go. It works well in my Dart.

5.7 block crank
eagle heads
6.1 camshaft(New Push Rods and Lifters)
long tube headers
Maybe a tune to run e-85

this is on the real cheap. there are more cam choices out there that will net you a very good return but its all in how much you want to wake it up. I went to the point of premium gas, not race gas. this is just my two cents and really does not account for all the guys that have dug deep to pull great numbers out of these with better cam selection.

so far it sounds like for the modern guy the sky is the limit with these motors and still keep the drivability and mileage.

just my limited knowledge on the gen 3 in my car.