I have a 06 5.4 scab 4x4. I currently have a 40 series flowmaster y'ed out the back. If i cut the cats off will the check engine light come on? I used to have a 04 gt and installed a off road x pipe and the light came on so i turned off the rear o2 sensors with my programmer. Will i have to purchase a programmer or o2 simulator to get the light off if it even does come on? Thanks for the help.

 

Honestly, I wouldn't mess with it. The Mustang crowd does it all of the time, the truck guys really don't do it. If anything just go with a set of high flow cats. I really don't have the information to say whether or not you'd be gaining anything or not. If you want, give Justin at VMP Tuning.com a call and he'd be able to tell you if you'd be gaining anything.

 

Replace them with two hi-flow cats, much better off.

 

Is that California Smog-legal?

THis is what I currently have.. + JBA headers



Replacing the 4!!!! cats with 2 hi-flow would definitely be the last piece to the puzzle!

 

Your cats are at the rear of the truck? What kind of mufflers are those..?

 

Oh, no... haha

I asked if replacing the 4 cats with 2 hi-flow was smog legal in california. Im just saying, I have a very hi flow exhaust, 2 hi-flow cats are the missing pieces!

They are "coffin" mufflers. THey are shaped like coffins is you look at them from the side. The are basically a free flowing muffler. They have some fins inside to direct the air, but there are no "chambers". THey have a deep Growl sound to em.

 

I have never seen, nor heard of those before, so I was like wtf??

I believe I read somewhere earlier that cat modification is illegal in California. Best bet is to do it yourself and hope it works ( and you dont get caught, the fine is pretty far up there ).

I found the thread about cats in California, here ya go.
https://www.f150online.com/forums/sh...d.php?t=338367

 

Haha. I live in CA as well (Huntington Beach)... I just pick up some magie high flows # 94306. It will be very tough for you to find a shop to swap out four stock cats for two high flow non obo-2 complaints. Most shops will only do the swap if you have the expensive OBO-2 complaint cats. I did find a shop that will put the #94306 in but it will cost me a lot of coin. The 94306 will not throw any codes as long as your o2's don't have a lot of miles.

 

fordboy does that x pipe make it any louder?

 

What name brand do yall recommend?