bigbaddiesel

im gonna hollow out the cat this weekend. I see the muffler, which is farthest back from engine, and then about 1 foot away, i think its the cat. thats all there is on the exhaust pipe. from there on up to the turbo its clean. Ive heard of a resonator (i think.) I just dont want to start sawing away and then find out it was the wrong thing

vssman

The cat is the round thing that is closest to the engine. It sit under the passenger side of the cab and has a taper to the front of it.

bigbaddiesel

cool, there she sits. Now i just gotta figure out how i want to do this. I dont have a welder, but a friend does. perhaps i can rig some sort of deal with clamps. I can figure out something. thanks for the reply.

98rammer

i did mine at the beginning of summer. i took a crowbar/pinchbar/prybar- whatever you want to call it and went in through the 3&quot; side. it helped a ton that i got a big hammer (the smaller sledgehammr types). it's a pain to go through, but once you put a hole through the middle, the rest will start to crumble and fall apart easy. just don't breathe that stuff.<br><br>Tom

BIG&BAD

what will that help? will it improve air flow??<br>

DieselDaze

I decided to keep the Cat but remove the gutts.<br>That way, if you look under the truck, it looks all stock. <br>What they dont know is, the cat has been hallowed out.<br><br>Now, to do this is a different story!<br>It took me and my good friend about 4 hours to get this done.<br>The cat was heavily rusted on the exhaust pipe. We used torches, hammers and an air grinder to get the cat free from the exhaust down tube.<br>Once it was free of the down tube, we left it attached to the larger diameter tube leading into the muffler.<br><br>Once we got it free of the down tube, what we found worked the best was the handle from the floor jack. <br>We took the hand out of the floor jack and used a rubber mallet to pound the jack handle into the honey comb catalyst.<br>Working the jack handle in circular motions, we were able to break out most of the catalyst. <br><br>When the catalyst was gone, we placed the cat shell back on the exhaust down tube and tightend all the fittings.. and off I went.<br><br>Looking at the honey-comb matterial, most of it was plugged up pretty good. I'd guess that a little less than half of it was plugged with black soot.<br>This means that only just over half of the exhaust was flowing through without impedence.<br><br>I did not notice any performance gain post cat modification. I do not have a Pyrometer either, so I cant address the exhaust temps. However, I would have to assume that the exhaust temps have gone down with the removal of the restricing honey-comb catalyst.<br><br>One thing to note:<br>The trip I took to California (Pre modifying the cat) I got 20 mpg. <br>The trip home (Post modifying the cat) I got 21 mpg. <br>There were weahter differences and traffic differences that might be relavent, or maybe it was better mileage due to the increase exhaust flow. <br>I dont know, and Im not trying to tell you that modifying the cat will give you better mileage. <br>That is just what it &quot;seemed&quot; to do for me.<br><br>Rich.

sixtogo

Cat removal made no diffefence what so ever on mine. The truck had 155K on it when the Cat was pulled. IMO it was a big waste of time and effort. You could easily see light through it, keep in mind its built in a &quot;corregated&quot; manner and if you look through it at an angle it appears clogged. <br><br>On gutting a Cat. The Cat has cadmium in it, a cancer causing &quot;heavy metal&quot; if you gut it do so in a manner that all dust/debris are contained. WEAR A DUST MASK! I would not mess with it, if one were found on the road in pieces Haz Mat would be called! <br><br>Michael

DieselDaze

<br><br><br>Ah ha! That it explains it! <br><br>We were very careful when we did that.<br><br>Rich

nevrenufhp

Or take a 5' piece of 3&quot; pipe, 2- 3&quot;OD connectors, 4 clamps, and loose both restrictions. It took me an hour to do last week. As long as the windows are up the noise is barely noticeable 8).

MnTom

Tell ya what guys- My cat did plug.I could not get any boost, egt's were through the roof. If I put my throttle to the floor and counted to three the pyro went to 1000*!!! It is amazing what an 18&quot; long 1&quot; dia. masonry bit can do!!

dodgeman01

same thing that happend to Mntom happend to me. It started out frrling life the truck was loosing power then the egt's started riseing.<br>Aaron

tmiller24

Hey BigBad,<br>I took the cat off my truck when the truck was stock and immeadiately noticed a big difference in the power and the sound of my poor old choking 95. I dragrace and had some Hooker Header 4 to 3 reducers around that were purchased for something else, They worked perfecy for making a &quot;test&quot; pipe. This was done 3 years ago, but recently replaced with a complete 4 system. Wish I had saved my money and bought the 4 from the start.