Intrinsicate

I have run my '88 without cats for a year, now, and love the sound and feel of the car. Last week, it sailed through Nevada emissions testing (fortunately, there was no visual inspection!). I have heard mention of owners "gutting" their cats, so they would still pass a visual: what is involved in this procedure? Does anyone have first-hand experience?

Jack '84 928s

you can also buy fake ones somewhere that go over the pipes. I have seen them but dont remeber wear.

hacker-pschorr

My friend gutted his cats with a long screw driver, pry bar, lots of beer, and lots of swearing.

I'm pretty sure this is the method described in the Workshop Manuals.

Sean79 5spd

Piece of rebar and banged the hell out of them with a hammer. This was on an RX7 but same procedure applies to shark.

SteveM928

I usually use a fillet knife. Make sure it's good and sharp. First you turn them upside down... oh... wait a minute... you're probably talking about catalytic converters. Never mind.

hacker-pschorr

SteveM928,

You forgot a few steps - bottom of the page:

https://rennlist.com/forums/showthre...&highlight=cat


Intrinsicate,
That above thread is covering the same question on the 944 side.

SteveM928

Obviously great minds really do think alike.

T_MaX

Gutting a Catalytic (Cat) Converter

Sorry to say this guys, but the old way of gutting a cat will not work on these cats. Well it will, but you will end up with more restriction than you started with.

Here is how I did mine:

After removal, I used a plasma cutter to cut the top quarter off the three cells in one piece (per side). From there I used a number of tools to remove the ceramic and stainless steel mesh. After everything was removed, I mig welded it all back together.

This worked well, even with the car on a lift you could not see that the cat had ever been modified. After a few hundred miles (Track Miles), I decided to change the configuration up a bit. I did all the above and this time I took the guts of two cherry bomb glass packs and installed the tubs and glass in each side of the cat*.

The db's dropped a little and the tone is much smoother than with the cat's just gutted.

Combine the above with an RMB and enjoy

P.S. The next experiment will be a better X-over before the Cat/Glass packs installed on stock (like) down pipes.

NOTE

* Stainless Steel safety wire was used to hold the fiberglass wrap to the tube and the Cat’s had to be cut on the ends a little more so the tub could be mig welded on two sides.

** This was done on a spare Cat. that had been deemed "defective/bad" and is not used on pubic streets or Hwy's.

*** Modifying your Cat's could be a violation of Federal and/or local Laws.

Jim @ EuroWerks

My eyes are burning from the tears that have now washed the dirt from the day into them. If you can't tell the diff between cat, chicken, or rabbit, whats the diff!

Giovanni

They all taste like chicken!

Jack '84 928s

Mine ran so much better when i cut the cat off, probably because it was clogged and leaking lol. Felt like i got 30hp+ lol. Oh and where i live i had a muffler shop take it off. heh.

steveZm928

I have been around rennlist for a while and have noticed quite a hatred for cats. People are constanly talking about gutting them and such. Then ther was the Ford Ka commercial where one was decapitated. Lay off the cats guys.

steveZm928