As a profesional mechanic for many years, I can tell you, there is no free lunch. Any modification that increases performance will end up as an increase in fuel consumption or a decrease in longevity. The mfg's spend millions of dollars trying to balance the fuel consumption vs. Power of modern engines. There are many mods one can do to an engine to up it's performance, however one can only run an engine so lean before cylinder temps start to erode longevity. More power equals more fuel, period. I built many performance engines over the years and have found this to be true in 90% of the time. JMHO...but any experienced engine builder will back up my words.
