svandorst

Hey guys, so yesterday my car started getting this annoying *** rattle-y sound coming from the passenger side so I get out to investigate..I determine its coming from the cats (got the dual-cat setup). And just tonight my dad and I went to our car meet/get together spot and all of a sudden the rattle goes away but now all of a sudden the car runs like absolute garbage. The sound is wayyy off, the car feels like/sounds like its running on less cylinders..so I'm pretty bummed about how the car is performing.

So do you guys think that maybe the core deteriorated and was rattling around inside the casing, and then lodged itself in the way of my exhaust flow? Any help would be appreciated thanks.

gmstrong

take it apart and take a peice of rebar and hollow out the cats.i did this too my tbi 350 before i sold it,it made pretty big difference power wise and sound wise.

svandorst

This is along the lines of what I was thinking of doing until I have the proper funds to replace both of the cats at the same time. I live in california so its a must for the whole smog thing..how would I go about pulling them apart? Unbolt the y-pipe from the exhaust manifolds, undo the slip fit clamp to the intermediate pipe and drop the assembly, and try to open it up from the top? Then I'll need new gaskets for the exhaust manifolds when it has to go back in correct?

Thanks!

gmstrong

PB blast the **** out of all of those bolts.Let it sit for a hour the longer the better.But they will mostly likely break any way might be more of job then what its worth.I think you have 2.75 inch pipe from the cat back cut off the cats and add straights depending on how long they are flowmaster makes slip fit connectors but their like 10" long i never messed with fbody exhaust.Im used to trucks those cats on them are HUGE mine was 30 pounds and 20 inch long.talk about clogged.i have pic if you want to see it.

svandorst

lol no it's alright I believe you. Yeah see I would straight pipe it but since I'm in california that's not much of an option for me when the sniffer test comes up..I just don't have the funds right now to afford replacements so I assumed just gutting them out to stop the car from running so shitty would tie me over until I have the funds. What would really be nice is making flanges for my y-pipe and cats so I can run straights in between sniffer tests (with the stock heatshields welded over them so they at least pass visual), and cats when I need to get my smog.

This just had to happen on my weekend too..wtf

camarosrock1989

iTrader: (1)

gmstrong I would love to see picture's. I have my Cat just have not replaced it yet.

one92rs

iTrader: (5)

remove the exhaust from the manifolds or n front of the cats if possible and start the engine. then rev it up. it should be slow to rev right now. also if you drive it right now for enough time to get hot and have a way to check temps you can do that. it will be really hot in front of the cats and cool in the rear.

svandorst

I'll be able to check that out tonight. In the mean time, can you or anyone help me find which magnaflow replacement cat to get? Its gotta be one of those california 30000 ones but idk if its the 2.25" or 3" diameter ones I should be getting. Everything from the cats forward to the exhaust manifolds is stock, and I'm just trying to replace my faulty one(s).

kiss4afrog

If your set up uses a single converter it would be a MagnaFlow 36019

If it has dual cats, MagnaFlow 36015
These would be direct fit slip on style cats. You can see pictures on almost any parts store web page. And yes, they're approved for sale in CA.

Measuring the temperature in and the temp of the cats body is a way to tell if it's working. The body should be at least 30 deg hotter but not more than 200. Somewhere around 200 deg you would likely have a rich running condition as the cat is working to hard.

one92rs

iTrader: (5)

the degree of the cat will depend on usage. idling prolly so. running the car around it is going to be hotter. will also depend on if the exhaust is completely stock also.

svandorst

Well I bought myself a little bit of time to weigh my options until smog time comes around next year. I was on the freeway, decided to put the pedal to the floor and just held it for maybe 10 seconds then I hear a loud *POP!* and then the car begins to accelerate like normal. Guess I blew the clog out, car runs like normal now (granted it is a little louder).

I was thinking of just doing headers/y-pipe, but since I don't have that kind of money right now I can save up for it and just drive the car the way it is now since there's no more blockage.