Little Black Pebbles?
 

heard some rattling comming from my exhaust pipes so i set it up on jackstands today and unbolted one of the junctions, shook it around a bit and small back pebbles fell out. in all it was a small handful of them but where did they come from? the Cat mayb?

You cat is toast. Same thing happened on my kid's 84 NA.

What we did on my kid's car was to take the cat off, then using a metal fence post, take all the remaining charcoal (or whatever it is) out of the cat. That stopped the little black pebbles, and have it a nice throatier roar.

Or, conversely, you could by a new cat.

Going green is overrated.

Poke it out with some rebar from Lowes and pull the honeycomb bits out. Cheaper than aftermarket exhaust. You still have the muffler so it won't sound overly tacky.

Wear a N95 dust mask if you do. The ceramic dust is super fine and really nasty. I didn't and I was coughing up congestion for weeks. It doesn't take much. :( There are 3 layers you have to bust through, so there's alot of catalyst that has to come out.

CAT woes
 

First: Modifying a cat is a violation of FED law. You should replace it with a good cat. Should you modify a cat...you would be foolish to publish such information on a public forum. Used Cats cannot be bought from boneyards, but can be bought from private individuals with parts cars and some individuals HAVE purchased entire parts vehicles for the cat alone (price a new one and find out why) There are after market cats and cross matching cats that fit but installing one of these may violate local or fed laws as well (or so i hear)

Later...

In other words, its not intended for use on public roads wink wink.

Gotcha.
 

Riiight...now we are getting the hang of it!

haha, well i guess itll just have to stay toasted then. i saw some of the aftermarket ones lindsey racing sells a high flow replacement that ill get when i can.

I replaced my cat with a universal one from the auto parts store along with a new o2 sensor to pass emissions. They make the universal ones at different lengths.