shiftdrift06

iTrader: (24)

I did some searching. And couldn't come up with a definite answer. So,

I was wondering, which part of the cat is "secondary" and "primary". I have a set of gutted cats, and it looks like the, "metal honey comb" is still intact, but the other section is gutted out.


Also, I was wondering, if I could take it to local muffler shops and have them install. But would they do it, or report me for having them install modified cats? Also, how much should I be looking to pay to have them installed? Thanks.

undrgnd

iTrader: (2)

Your searching sucks, but anyway... There are are no 'metal' honeycombs on our cats, it's all ceramic. The primary portion is the front portion, which is the part closest to the 3-bolt flange. The only way the muffler shop could tell is if they looked inside with some type of instrument, which is unlikely. If you did a good job cleaning out the secondary and there are no remnants or other loose pieces in there, you should be okay. Worst case, if they found out and said they would report you, you act like you didn't know and tell them to put it back. What is going to be your reason for replacing the cats in the first place? THAT may raise some eyebrows. It's not like they go bad every day. I've had them on cars for over 250k miles and they were still going and going...

However, not sure I would trust someone else's work on illegally converting a cat, you don't have a lot of recourse. Get a buddy and replace them yourself. Unless you're not mechanically inclined and have no hand tools, it's pretty straight-forward. You'll need an O2 sensor socket, some common size (10, 12, 14, 15mm) sockets and wrenches, a looooong extension, a small screwdriver, a 3/8" drive ratchet, and depending on the age of the car, some WD-40 or equivalent. Count on getting dirty, and make sure the car is secure on the jacks before you get under it.

davidv

iTrader: (2)

Like undrgnd says. The primary portion is between the oxygen sensors.

allenp20

iTrader: (4)

for the amount of the install I would just save up for some test pipes and install em your self

undrgnd

iTrader: (2)

What does that have to do with the topic? Maybe he doesn't want to hear that crappy sound or deal with CELs or stinky exhaust. And it's the EXACT same amount of work whether he installs test pipes or HFCs or gutted cats.

gothchick

iTrader: (12)

LMFAO!! :-)

Gutted cats won't flow as good as test pipes... The empty volume and odd shape of a gutted cat will mess up the pulse waves & exhaust scavaging. Some of the better test pipes step up in volume a little, but no where near as much as a gutted cat... Just my 2 cents.

GrayG35

iTrader: (2)

mine are gutted and it was more than worth it. i noticed gains on the first day and even more after 3 days of having them on and the ecu learning it. just use some spark plug non fowlers and you wont have any cel's. oh and ask the muffler shop to rip all that metal stuff out. they had to cut out the top of the cat where the metal stuff was in order to get it all out. mine cost 80 with gutting and reinstallation.

BeejZ

iTrader: (1)

I gutted mine as well, just for the sheer fact that is was free. Was not that easy though. I did have a metal honey comb insite mine, it was the hardest part to remove. It was definatly a pain. I did feel noticable gains as well. May not have been as much as test pipes but all it cost me was my time, and that is free as far as I care.