My 98 f150 had 135k on it before I changed my exhaust with a custom one. Ford motorsport shorty headers, 2.25" piping into high flow cats, custom x pipe, out the side like lightning with flowmaster mufflers. Then i had the 4.6 tuned up with Mike T's kit, denso plugs, accel wires and msd coil packs. I also have the xcal 2 already. Before the tune up and exhaust if i floored it i'de get a slight ping at around 3500rpms and not rev higher then 4k.
Last night, i floored it at a light just to see what the acceleration was like.

MY GOD! Truck took off like its never have before, rpms climbed to 3500,4000,4500 and hit over 5000k before i let off. No pinging what so ever, no smokey exhaust at the high rpms and speedo was near 50mph before the tranny shifted to second. I was in complete amazement. Then i started to wonder what would happen if i actually got off my but and changed the O2 sensors and got a clean filter for my AF1. Cause i know its holding it back some.

 

Whats a Mike's T kit? Sorry Mike T's kit.

 

www.troyerperformance.com (Mike Troyer)

-Brian