actually, I gutted both my cats.

I gutted the secondary portions of my catalytic converters last week. I was tired of my test pipes raspy sound. I did this in preparation for my ATI procharger install, I also added on O2 sensor bung & wideband sensor, along with a Zeitronix & LCD display. My supercharger is going in this week. I dropped my car off today. (sunday 6/12) No more raspiness or gas smell!!
I'll be posting pics of my procharger install later this week or next.

 

I did the same thing too, oh wait!!!! You mean on your car!

 

I did the same thing too, oh wait!!!! You mean on your car!

 

i saw that same thing on my alien autopsy dvd

ps oh great now that nasty picture is going to be in my thread!!!

 

what steps did you take to gut them? do you notice an Hp difference? id like to do that too...

 

I used several different sized drill bits, with a extension.
I have lots of old bits from my workshop.
A 3/4" spade bit worked well to blenderize the clumps.
After drilling & blenderizing the middle section, I used a chisel to seperate the honeycomb from the inside wall of the cat. It took about 1 hour for each, kind of messy & I used alot of elbow grease. It was worth it though.
Slightly deeper sound, not much of a change, but no raspiness or smell

 

your coming from test pipes right? so you have same gains or similar gains as test pipes? or not much of a change from stock? i wanna know if its worth it to gut them out...

 

No noticable change in power, plus or minus, from test pipes. No dyno to back it up.
I did it more for the sound, smell & emmisions testing.
Also with my new supercharger I wanted my cats in, then tune it.

 

im def gonna consider this now. seems better than test pipes and cheaper haha. esp in Ca. if i get pulled over ill still have my cats "there"

 

ya, plus you'll still have your primary element in there doing about 65% of the job

 

But you are stuck with the G forever, as you can be made [by courts] to restore it [emissions]to exact oem if you sell it and get caught even 7 years from now........the seller/original owner is always tied to emission violations...........unless you wash it [liability] by selling/trading to a dealer who is legally obligated to check such things........but they can sue you after the fact to pay for restoration to oem in most states.

 

I give 2 thumbs up to the gutted cats. I had an extra set and completely gutted them, primary and secondary. No rasp but there is a slight gas smell, but not as noticable as with the resonated test pipes I previously had. I wouldn't recommend doing this to your only set though, for reasons stated by Q45tech. It sounds like stock but is noticably louder. Combined with the pop-charger this mod took .2 seconds off my 1/4 mile and added 2 MPH to my trap speed.

 

I did the same to my high flow cats, congrats on a job well done! Trust me, there are plenty of used oem cats waiting to be sold for cheap.

 

ya not hard to find used oem cats. especially junkyard, and more and more people crashing their G's/Z's sadly... but cant be hard to find. if you gut secondary, you wont pass emissions for sure?