nolanr0413

I just got the car outta storage today , and i was gonna grease the front end only , b ut i decided to gut the cat if i could get the blots off. I did get the bolts off and i gutted the cat . It was about a two hr process. I used a big *** drill bit to get the honey comb out , thats like the only way . A hammer and chisel sucked ***. heres a few pics.

nolanr0413

gutted cat .

nolanr0413

and heres whats in it. I cant believe a cat looked like that . It is like concrete and it looked liek screens at each end . But its sold all the way through.

MikeC.86Roc

iTrader: (10)

I did the same thing on my old cat.. I even knocked the bar in the center out with a screwdriver, chisel and hammer. Took a while but I got it.

I would bet most of these old thridgens running around are homes to the kind of crap you found in yours too.

GTA4ME

I need to do that to mine.

IROCThe5.7L

Knock that bar off in the middle. Then you can run a pipe though it

SuperchargedRS

The only good cat.... is a dead cat lol

nolanr0413

im gonna leave the bar, i really dont car about performance that ill gain, this 305 tpi suck. gm shoudl be ashamed they put the enigne in cars, I m gonna do a 350 or 383 next year , so im saving money for that and not gonna put any money into performance engine parts.

IROCThe5.7L

But your car will sound better with a pipe in there

trueburton

What size pipe do you need to put in there. Weld it in or what? Shove it from one end to the other or just cut the cat in half and put back together?

LedZep

iTrader: (22)

Whats better to run a short high flow cat or the big *** stock cat that has been gutted. I have both, but I was told that the gutted stock can actually hurt performance through turbulence? And that the high flow will have a better sound and perf than the gutted stock since its so large.

nick418

The only good cat.... is a dead cat lol


hehe ur deff right my friend


just plant a tree for the enviroment next

IROCThe5.7L

Thats why you run a straight pipe through it.

SLP IROC-Z

iTrader: (1)

id definitly put a pipe in there or just use a test pipe. the gutted cat causes lots of resonance. i ran off for a while then put a pipe in its place, much much better.

trueburton

i am having a hard time getting the cat off the pipe it is coupled over and clamped. I have heated it with a torch and pried at it and hit with a hammer and it won't come off. any one got any tricks?

nick418

i had a hard time as well,,,,, and have dual cats! which means even a longer project. Its worth it tho! ESP IF UR A EMISSIONS INSPECTOR!

trueburton

well i got it off. I used a block-n-tackle to pull it off. worked great.

LedZep

iTrader: (22)

but what is better a gutted stock or a high flow. I dont want to cut it open and put a pipe in.

trueburton

i just put a pipe in mine today without having to cut it all open. the gutted cat with a straight pipe would be better than a high flow and a lot cheaper. just gotta be careful cause the gutted cat with pipe is illegal.

LedZep

iTrader: (22)

I already have a high flow cat and a gutted stock, again my question which would be better to run. A stock gutted with no str8 pipe or a high flow????

trueburton

not sure what would give better performance. i would geuss the high flow would. the high flow will however definitly sound better. if yuo already got a high flow i'd put that in.

D Stroy H8

What size pipe is needed to pipe the cat? I have dual cats, and would LOVE to straight pipe both of them. They don't function anymore anyway.

trueburton

i used 2 1/2 in. muffler tip extension. one end is partly flanged and makes a better fit. you then need to get a double female coupler and place that on the other end after the pipe has been cut to length. then use a heating torch to heat the end and flare the end out a little more. then slide the pipe through until the flared end lodges itself nice and snug in one end. at this point you want about a 1/4 inch hangin past that first small flange on the back of the cat. then heat that end and flare it out using a hammer and broad punch. now the pipe is in place and you can weld it in. or use JB weld like i did. worked great and my exhaust sounds sooooooo much nicer now. i get many compliments on how my exhaust sounds. hope this helps any questions you know where to go.