I just wrapped up the installation of my Stage 2 package from TP on my '03 Offroad 5.4, and I have to say that although it was a challenging adventure for an autobody specalist, it was worth the heartburn. Lookout Chevys. I don't even have my tunes yet, and the transformation is unreal. I added the 75mm throttlebody to the mix, and the only test run I made before I was done was the cat-back Mag si-so addition, so as far as the impact of individual components is concerned, talk to the dyno guys. Some tips from a guy fresh out from under the hood: dont even consider putting E-fans on your rig using any kind of push pins or ties with the radiator in the rig. ( PERIOD ) Do use heatshrink butt connectors and terminals. I have set up police and fleet vehicles for 31 years, and installed every kind of electrical aftermarket device you can imagine, and the guys I worked with over the years have all learned that the #1 failure of this stuff is poor grounds and poor connections. It doesn't just effect the device, it'll drive you nuts with feedbacks in other circuits. Always use external tooth star washers between ring terminals and ground surface. When in question, go to a factory chassis ground screw and piggyback your terminal there.

 

i had to replace a relay, relay block and manual switch this weekend on my efan.. turns out i had an underated switch at 10Amps. so it worked for about 5 months till it finally burned up. then basically made the relay block store alot of the power till it finally melted