Hollowed out Cats?
 

I plan to either trade my car in or sell it in about a year or so so im trying not to do any major mods to it so it will hold its value as best it can. So far all i have done is my stripes and a k&n but now i kinda want a louder exaust. I called up the local shop who happens to be very reputable and the owner told me he does all kinds of mustang work. I told him what i wanted and he told me he could put some flowmaster mufflers on it and hollow out my cats so that they would look like theyre still there but they would actually be hollow. He said that would give it a nice deep sound, which sounded good to me at first, but then i thought about my oxyagen sensor. Isnt that in the cats? Does that mean my check engine light will be on all the time? I need some advice aout this before i decide what to do. Thanks for reading, i appreciate the help.

You should have a set of o2 sensors before and after your cats, threaded into the bungs on your h pipe. It would be the same as running an off road pipe, and you would need MIL eliminators to keep your check engine light from coming on. You can get a set of the splice in ones from PEP (http://www.ponyexpressperformance.com/index.html), or you could opt for the easier, but more expensive, ones that you plug in between your sensor and the harness. I personally made mine from a diagram and instructions on a website. It cost me all of about $10 in electronic parts from radio shack (aside from the $10 soldering iron I bought). I will see if I can find that site again. If so, I'll post a link. It was rather easy to do. I took pics, but when my computer crashed, I lost them.

I have mine hollowed out. Had the X pipe but was to loud with the vert. Just do the mil eliminators, find them used on the other mustang boards ( mustang world,modular mustang etc.. ) or e-bay. It will sound and run better and still look stock!

Thanks guys, i think thats the road im gonna take, i appreciate the help.:D

hollowing the cats is a waste unless all you want is more noise

and imo it sounds like ass why dont you spend the same money on a h/x pipe and save your stock one for when you want to get rid of the car

hollowing the cats is a ricers trick that is not going to gain you much but a crappy sounding car

Unfortanatly I'm not too familiar with the h/x pipes. Is it a weld job or a bolt-on for the exaust? I am assuming i will still need the MIL eliminators. And if i get a h/x pipe, will i still need mufflers or will that make the difference? P.S. i am mostly just doing it for the noise, but i do want the car to sound as good as it can without having to buy a whole new system. Thanks.:)

Just have the shop weld in some flowmaster or mac mufflers. Leave the cats alone!

If you hollow out those cats your gonna get a nasty high pitched raspy sound... yuck! And depending on where you live, you wont pass smog with MIL eliminators... by the way, using those messes up your air to fuel ratio!

Just cut out the stock mufflers, weld in the new ones and your all set :)

Oh yeah...

H and X pipes are completely bolt on.. easy to install.. BUT you dont even need to go that far, especially talking about getting rid of the car soon.

Just do the mufflers, you will be happy with the sound. Flowmaster or MAC will give you a much much deeper & louder sound! :)

So confused...:confused: Ok, thanks man, i think i might just get the mufflers to start with, then if i want more sound and have more money ill go with the x/h pipe. I appreciate the explinations though, thanks again you probably saved me some money and problems with my car.:D

you will need some mil elims if using off road x/h pipes or you can get the catted ones and no most of them do not need welding it is a bolt on

it unbolts from the stock headers and cat back and drops out and the rebolt the new one in

and no it will not mess with your air fuel ratio

aqnd for the smog test that why I said keep your stock one

Cool, thanks man. Allright so heres the plan:
Phase 1: Flowmaster Mufflers
Phase 2: h/x pipe.
Phase 3: Cobra :D

perfect! :)