Bigger motor or mod it?
Blower won't hurt your mpg's nor will a turbo. What hurts mpg's is how hard you mash the gas. The bottom end is fine for a 8psi. 10psi with other supporting mods. Twin screw blowers such as the KB link posted are very efficient. A turbo is most efficient as its free power so to speak. If you can fab your own turbo kit like lucky13 then you have got it made. Beware boost is addictive!!!
Thank you sir. There's more to come. Going to put the truck in the high 12's this spring and shooting for mid 12's by summer. Stock 5.4 can handle 500rwhp and even a bit more but it's a ticking time bomb. At the advce of Mike Troyer I'm going for 470rwhp.







