I have a 2002 5.4L supercrew and am wanting to add a set of long tubes and high flow cats ( already have these picked out). I need to know everything that I need to do in order to not have any cel troubles. I currently have a SI/SO maggie(22") that was installed about 8 mo. ago. Can I continue with this if the true dual set-up will not make much difference in performance? Or get a di/do or di/so. w/ x-pipe.

 

Long tubes generally need a tune to compensate for them. Not to mention a tuner is going to give a lot of gains, performance wise, among other things. Check out Justin at www.VMPTuning.com ..

 

Custom tuner is among top on the list. Am also thinking about u/d pulleys and 75 mm throttle body. Does anyone know if the t/b is worth it by itself or just leave it alone? Already have AF1. Was wanting to get most of it installed and then get a custom tune.

 

Don't waste your money with the TB. I'd get the UDPs and E-Fans as well.

 

I have thought about e-fans, but do not know which ones to buy. I have heard some bad things about the ones from Troyer. Suggestions, please.

 

Long tubes here!
check out pic's

 

I have seen both underdrive pulley systems and the BBK lightweight pulley systems. I was wondering what the power gains were significant from them. ?