do0dfromcali

I was wondering if anyone knew of a link that showed how to gut the cats. Is it a hard job to do? If so, does anyone know of anyone in the chicagoland area that will do it?


Plus...is the SLP LM with gutted cats asking to be rolled by the police? <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

BuckeyeROC

iTrader: (7)

Don't know if there's any difference in the LS1 cats from my 89 IROC, but here's what I did for that car:

Put on a mask b/c the dust is not healthy. Unbolt the exhaust at the cat(s). Take a tire iron or large flathead screwdriver and a hammer. Pound on the tire iron/screwdriver to breakup the insides of the cat. Do it until all the stuff is broken up and then rev the engine a few times to clear it out.

Or just get an off-road y-pipe.

Bad Blu Formula

iTrader: (3)

That all takes too long. Do this. Take the y- pipe off and use a drill with a long drill bit and drill all that crap out. That'll be way faster than hammering and possibly cutting your hand. After you drill most of it out you can use a tire iron or whatever to get all the little stuff that you can't reach. For that one cat that you can't reach with a drill, cut the pipe a little before the cat and then hit it up with the drill. You'll have to weld it back up later but thats the easiest way that I know of.

00silverz28

iTrader: (6)

I've got some gutted cats sitting in my shed that came off my 2000 Z28. They are for sale if you want them. That way if you didn't like the sound you could just put your stockers back on. Send me an email to steve_howell78@yahoo.com or pm me and we'll try and set up a deal. Thanks alot.

steve

do0dfromcali

So the off-road y-pipe is in place of the cats then?

If so, how hard is it to switch them back and forth in case of emissons?

jimmyblue

iTrader: (11)

Most off-road Y-pipes are meant for headers.
If you have cats after headers they are in
the Y-pipe.

The stock cats are in separate pieces of
down-pipe that are bolted between the exhaust
manifolds and the stock Y-pipe. If you're
talking about the stock cats here, then most
ORYs probably won't even match up.

One of the stock cats is pretty accessible
(especially if it's off-car). The other has
bends before and after the cat and is going
to be tougher to handle.

The ceramic is pretty tough stuff and will
just chew a regular high speed steel drill
bit. A long masonry bit (carbide) might last
through the job before needing to be
resharpened. A hammer drill might be the way
to go.

The best way to get through the ceramic is
by fracturing it. A sharp chisel, along one
of the square planes, is your best bet. A
long shank one. Or even a piece of hard
steel rod ground to a point. You want to
concentrate impact stress. An air chisel
will save you some sweat. I've busted out a
cat with just a crowbar as a long-*** chisel,
and it took me a good long time.

Which do you mean, stock cats or header cats?

2000Firehawk

iTrader: (248)

<img border="0" alt="[bullshit]" title="" src="graemlins/gr_bs.gif" />
Stock cats breakup real easy. Best broken with a 1/2" wide 8" long wood bit. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> Takes 5 minutes to chew thru each cat.

Dave

jimmyblue

iTrader: (11)

I'll have to give that a try...

CashDudeHomie

iTrader: (5)

I think the best way to do it is to cut each cat as close as possible and remove it. Then knock all the **** out. Then open each end up just a bit with a hydraulic machine and put a piece of pipe thru the cat and weld it up. Then weld it back on the Y pipe. Think about it. If you just knock half the **** out and put it back on the car, it is going to cause all kinds of exhaust turbulance. That is just my opinion.

mw02

Arent stock cats welded to the stock ypipe?

jimmyblue

iTrader: (11)

No, there are 2-bolt collar clamps that hold
the Y-pipe to the downpipes with the cats in
them. And these downpipes have a 3-bolt cast
flange mating them to the exhaust manifolds.

Some aftermarket Y-pipes have cats welded
inline. Off-road Y-pipes have no cats.