Sport trac upgrades

[TwoX]

Ok i just got my sport trac a couple of months ago, and so far all i have done is added a y-pipe exhaust with no muffler, k&n filter, and royal purple. What can i do to get it to go faster? and what are some other good mods for it. And does any one here have true dual exhaust? i know the guy at the muffler shop told me i had 3 cats and if i cut 2 off to make it louder i shouldnt hurt the truck? I was also planning on lifting the truck to fit 33's.
Oh and does anyone have subwoofers behind the seat with pictures? the audio shop said i wouldnt be able to fit them behind the seat even tho i took all the stuff and trim out. They said i would have to put one under the seat

 

[brianjwilson]

Try searching.
Taking some of the cats off probably won't do any good. They shouldn't be slowing you down unless they are clogged.
Be sure you don't over-oil the k&n, they are known to cause some problems with the maf sensor. A programmer will help performance a good amount, check out the xcalibrator 2 or 3. I think there is a tuner forum on here, James Hensen here is a good person to buy a programmer from.
Your truck is going to be slower with 33" tires, unless you re-gear your axles.
I don't believe there is any easy way to fit a sub behind the seat, but I haven't measured, looks like a bit of work to fit one there. I say put the amps back there and put a sub under the seat.

 

[Gregg XLS]

This guy has a sub behind his seat...I think it's actually a really good setup

http://www.cardomain.com/ride/2388971

Good luck

 

[Sams01XplrSprt]

I got single in and dual out 40 series flows and i still got the 4 cats in mine but i wanna remove like 2 of them.