3800 Gutting the cat

[Adam86]

i have the rt downpipe and the cat is busted. i noticed it the other day, when the exhaust wasnt as loud as it was before and i could hear a clanking when i would start my car in the morning to warm it up. there is also a rattling now when i turn the car off. i tapped the cat w/my fist and rattle rattle rattle. i dont have the $$ to buy a new cat right now, would it be hard to just gut it out and leave it like that untill i have $ for a new one? thanks

--Adam

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[GTPictor]

gut it and leave it alone no one will ever know and it better for flow (no by much but hey).

 

[Adam86]

is it hard to gut it out though? would i have to cut the cat off and then weld it back on or is it just clamped on?

 

[dole21]

chrys(12secgtp) did his last summer at lp's 1st mod day if i remember correctly.

I remember hammers and lots of pounding. hopefully he'll chime in here...

 

[GTPictor]

if its an random cat or stock one its a bolt on take it off long screwdriver hamer and knock the stuffing out of it til it all falls out then bolt her back up.

 

[Adam86]

how much stuffing is in it? lol im guessing that its going to be a bunch of metal shavings and crap that fall out when i rape it with the screwdriver, so i need to find my safety glasses or some sunglasses or something lol

 

[12secGTP]

yep.. i did it.
Big PITA. took me, hale, alex and someone else about 30 min to get the honeycomb out. Big mess too.

Flow better? yea. better than the clogged one
cause problems? yea. had issues with fuel trims and O2 readings and a host of other things related to the CAT (codes, etc). if you do this, make sure you have an O2 spoof for the rear sensor or you will have nothing but problems.
I also think that i had performance problems due to the exhaust flow since right in the middle of the flow, it expanded and slowed then tried to be crammed back into a 2.5" pipe. but if your not racing it should be ok.

all in all, it was better than the clogged cat I had, 200% better. but running catless or gutted cat has its issues if you dont plan for that.

you can get a perf cat here.... Carsound for pretty darn cheap. you want the 9400x series. the "x" is governed by the pipe size (most likely 5, 6, or 9).

HTH
Chrys

 

[J.E.T.]

Adam: If you want, come on over sometime and we'll work on the cat. I can't help but feel a little responsible .

But lets do the math first. $45 for a cat or $(almost the same) for an 02 spoof.

J.E.T.
'97 Red GTP