is it gonna smell any different or make any weird sounds? what could i use to hollow it out. like whats the best way to go about doing it?

 

a hollowed cat is worse than a test pipe. that area where the catalyst material used to be is going to cause turbulence for the exhaust gases. you want to keep the gases moving as quickly and smoothly as possible.

just leave it alone. i doubt you're going to feel the 2-3hp difference.

 

well im getting awful gas milage and im throwing P0420 or P4020 i forget which one. faulty cat functionality or something. i figured i would hollow it out and if its awful just get a test pipe after. how would i go about doing it?

 

it's not rocket science. grab a steel wire brush, jam it in there, and go at it like you're fisting a chick.

 

hahaha very colorful. i took out the o2 sensor thats on the cat and the tip is comletely white. so the engine code im throwing could be one of two things. the cat, or the o2 sensor. could a white tip mean the sensor is bad?

 

ok so obviously hollowing out the cat makes it a ton louder. annnnnd it is. so is there any way to quiet it down before i get a ticket? and yes....i know i should have thought of that before, but saying that doesnt help me now ha.

 

Hollowing out the cat probably wasnt the best idea but hey if its throwing a P0420 then more than likely it was a faulty cat anyway. I wouldnt worry sound wise, i doubt it could be that much louder than stock to fail a decibel test

 

haha. no it is actually a considerable amount louder. i do have headers and a full 2.5 inch cat-back on there too. can i put a resonator in there somewhere to quiet it down?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sickofitall1113 &raquo;</TD></TR><TR><TD CLASS="quote">well im getting awful gas milage and im throwing P0420 or P4020 i forget which one. faulty cat functionality or something. i figured i would hollow it out and if its awful just get a test pipe after. how would i go about doing it?</TD></TR></TABLE>

You do realize that Acura will replace a faulty cat for free on your 99 Integra, right? They'll replace cats on 11 years old and newer vehicles.

Seatbelts for the life of the vehicle too. I'm getting my 1990 Integra LS belts fixed this weekend for free, and its the stupid electric motors that went out, so it wouldn't have been cheap.

 

hahahaha ok well not anymore. since theres no way to prove it was faulty before i just hollowed it out. haha ohhhh well....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TunerN00b &raquo;</TD></TR><TR><TD CLASS="quote">

You do realize that Acura will replace a faulty cat for free on your 99 Integra, right? They'll replace cats on 11 years old and newer vehicles.</TD></TR></TABLE>

Thats true i didnt even notice he had a 99'. But oh well too late now, you can put a resonator on it if you like which usually cleans the sound out a bit making it seem quieter. Im running 3" turbo back w/ an APEXi turbo spec muffler no cat/res. loud as hell (not by choice) never been pulled over yet *knock on wood*

 

yea the state cops in mass, especially where i live patrol the main road in my town all the time.. i never really knew why, but they LOVE to screw people over for equipment violations. so now i just have to wait for my 6 more years of surcharges i guess. how does the resonator go on. like what area of the exhaust does it go onto and how does it attach?

 

Im assuming you have a bolt on exhaust system so really you would probably wanna either have one fabbed up to replace where your cat was orrrr your gonna be cutting up your exhaust a bit lol. I would recommend finding one that could be bolted up to replace your cat

 

i could just get a new cat. and avoid all of this, and the likely tons of money im gonna have to spend dealing custom work, which is always a pain in the ***. i dunno i'll have to think about it

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sickofitall1113 &raquo;</TD></TR><TR><TD CLASS="quote">i could just get a new cat.</TD></TR></TABLE>

That works too lol

 

I hollowed out my cat when i installed my turbo...

It doesnt seem to be much louder, but a turbo tends to do that.

I used a drill and some weird bit thing with a grinding stone on it, it had a point on it and it went right through it.

took around 45 minutes to do the whole thing.

 

yea i used the arm that jacks up the floor jack i have. i bashed it through the middle and once that happened pieces came out over and over. i got the mesh stuff out that coats the inner walls and i was done. half hour for me. not without a price though, i bash the knuckle on my thumb like 4 times and i sort of cant feel it that much now ha.

 

i hollwed out my cat in 10-20 min just get the big bar off of a car jack and just beat on fins and soon itll be hollow my exhaust wasnt much louder i think cuz i have the greddy evo 2 and it has a huge resinator but was a lil louder but i will tell u it smells the gases r nasty

 

please for the love of god, use punctuation. but anyway, yea i just went on like a 30 mile trip and it definitely smells really bad. im gonna look into bolt up high flow cats. anyone know a cheap one? gotta be bolt on though

 

ebay or omni has the adjustable cat..

 

Hope you saved the pieces lol... they have platinum in it