What would cause new Catco cats to have pieces break off internally?? My stock ones died a while ago, age was the factor no problem I had them replaced with 2 Catco cats. Not long after one of the cats began to rattle and you could hear a piece bouncing around in the exhaust making an awful racket. I finally had it replaced and yet again there is a *** awful rattling coming from one of the 2 cats again. I thought part of the problem was with my Eibachs and 16" rims the cats would scrape alot so I figured maybe that was the cause or maybe my cutout(near axle) I like to run with the plate off was causing problems?? I have 17s now and never scrape the cats and Im looking at replacing the entire exhaust using SLP Loud Mouth but I dont want to have to replace another set of cats so what else could it be thats causing me problems?? Also since I cant search at the moment is there a difference from the LT1 or LS1 Loud Mouth that would make either one a better choice to have custom welded up to my 92 Z28?? Anyone who has a 4thgen exhaust on their car your insight would be appreciated as would anyones opinions or experiences on the cat situation, thanks!

 

a few have put on LT1 exhaust cat-backs without too many problems. just re-do a couple hangers - a shop could do it. i say ditch the cats

 

No cats + Loud Mouth = Way too much unwanted attention. For now Im still passing the sniffer so I want to run cats for as long as possible.

 

I went through 2 catco cats whithin a few hundred miles when I had engine trouble. She was running rich and that killed the cats exactly like you described. Now I have a std. Midas cat in there and it has been fine - but Im considering removing it since it is not required for cars that old, here in Norway.
I got new catcos under warranty when they went out though - so I have one new in the box. I might be using that on my Tahoe when I install the Banks full exhaust on it!

BTW, any suggestions for a good high-flow muffler to put in on the IROC in place of the cat that is there now? No cat would be just a bit too much..



Ken

 

go for the ls1 loud mouth, all that the mffler shop has to do i make a 2-3 long section of piping to join the exhausst to the cat... using the ls1 is more straight foward that using the lt1... anyone has any input lemme know... i know someone here already has a loudmouth on his car.... we talked about this topic like 2-3 months ago...

 

I had the same problem with my Z. I replaced the factory cats at 195,000 mi. because my wife popped them on a speed breaker (good cats for the mileage I might add).I guess at 200,000 mi. they could be pretty well spent. I installed Random Technology cats. After about 1500 mi they started to rattle. I removed them and drove out to Random Tech's facility to let them take a look. They warranteed the one rattling and then asked me to use an infared thermometer and check the cat inlet temp, they should be approximately the same. Mine was about 90* cooler on the side with the bad cat indicating that bank was running rich. Possibly a bad injector or two. I'm leaving the cats off till I replace the injectors.

 

cats will not bad for no reason. they go bad from running too lean or too rich or form vibration or foreign object damage. mileage really does not affect them other than thier efficency. a GM engineer has told me that a cats efficency can be brought back up to like new by running the car on the freeway at a decent speed for around four hours.

 

I scraped my cats ALOT when I had the 16s and the Eibach Pros. Now I have 275/40/17s all around and gained alot of ground clearance and dont even come close to scraping on the same places I use to. So I dont know if it was contact or maybe running rich or lean?? I dont want to get a full new exhaust to have to cut it open to splice in a new cat. Maybe Ill see if they can make it so the cats have flanges on both ends and can be removed for a test pipe for the track with flanges as well??

 

go with the dynomax bullet or a moroso spiral muffler