Rotofire

i was planning on beating the crap out of my cats today and i got under there, and i don't know which on it is! what's with all the crap under there? it needs to be header-pipe-muffler....lol so simple. Well if rx7carl is reading this, which one is the cat? it goes manifold- short- short- long- pipe- muffler. do we still have the thermal reactors, my haynes manual is talking like we do well any help would be very much appreciated, i would like to know as soon as possible in that i want to take it out today, or at least beat the crap out of it and put it back on. thanks


edit: what will it sound like without cats?

cdrad51

If you have a '85 GSL like your profile says, it goes exhaust manifold, monolithic converter, monolithic converter, main cat, mid pipe, muffler. The Haynes manual refers to earlier models.

Rotofire

alrighty so what about the monolithic? what can i do with them? take a broom handle and beat the crap out of all of them?

edit: thanks cdrad

cdrad51

If you are suspecting flow restriction due to them being clogged, yes, the same procedure applies to the monolithic converters. If you don't have emissions regulations and have some cash, you can buy a racing beat exhaust system with no cats. That system includes presilencers - I don't think you'd want to hear what the engine would sound like with no cats and a muffler.

Rotofire

ah so i don't want to remove the cats and if i do just buy the RB exhaust system? (which i've considered) Oh yea i live in southern indiana where the cops are a little shall we say **** about that stuff....of course i'd like to see a cop try and crawl under my 7 just to check to see i have cats

cdrad51

Yeap, or, truth be told, you could replace the cats with a pipe also available at racing beat, but the noise will be higher than stock. But is definitely cheaper.

Rotofire

yea i decided to just leave the cats in until i have the replacment pipe in my hand and ready to do some damage. thans for the help but i think this thread is done, i just needed a little advice. Now i'm sure i will be on the look out for deals with exhaust. thanks again.

cdrad51

no prob.

cdrad51

To correct an earlier statement, the engine with no cats and a muffler is not that loud. Now that I have experienced it first hand, even though definitely louder than stock, it's not as bad as, for example, having a big exhaust leak.

cpt_gloval

iTrader: (1)

add a hi-flow header to that equation, and it's loud as all freaking hell.

Rx7carl

What usually happens is the 2 precats (the little ones between the manifold and the main cat) melt from the sxtreme heat. Then the chunks go downstream and clog the main cat. Couple of suggestions. First, exhaust work sucks anyway you slice it. The nuts will be frozen and you will probably break a stud or 2 or more and round off nuts. Be prepared to have the car out of comission till you repair whatever you break. Ok, now that you've been warned heres what to look for. Pull the precats, either as a unit (easier) or seperate. Shine a light into them and see what they look like. If they look melted, get a long screwdriver and hollow them out. Now look into the inlet of the main cat. If theres chunks in there from the precats, carefully remove them. If the waffle/brick in the main converter looks ok leave it alone. The problem with hollowing out the main converter is that you now have created an expansion chamber, which will slow down the exhaust gasses, causing decreased performance. Of course this decreased performance is better than a clogged main cat so let that be your guide. The "test pipe" would be a better solution (check ebay, people sell them on there all the time).