Melted cat substrate?

[VetteMed]

Took the passenger side exhaust manifold off today, for a few reasons: there was a crack in the case of the cat, and the rear of the cat brick looked kinda funny to me through the pipe. I banged the pipe on the ground a few times, and the cat brick came apart, and out came a few pieces that appear to be melted? or something melted on to it? Here's a pic:

http://i680.photobucket.com/albums/vv163/agchoset/IMG_2895.jpg

Any ideas what that's all about?

[GOLDCYLON]

When an impact occurs to the honeycomb material inside the cat it tends to shatter and break off into pieces that float around in the cat a while before the whole substrate desingrates. What you have there is evidence of melted substrate pieces that came into contact with a more eveningly heated honeycomb. they bonded back together. When my drivers side failed a few years ago it sounded like a chock full of nuts under the car. Upon removal of the cat the sunstrate material had rounded itself into a ball and was bouncing around inside the cat. Time for headers my friend ;)

[VetteMed]

When an impact occurs to the honeycomb material inside the cat it tends to shatter and break off into pieces that float around in the cat a while before the whole substrate desingrates. What you have there is evidence of melted substrate pieces that came into contact with a more eveningly heated honeycomb. they bonded back together. When my drivers side failed a few years ago it sounded like a chock full of nuts under the car. Upon removal of the cat the sunstrate material had rounded itself into a ball and was bouncing around inside the cat. Time for headers my friend ;)

Yep, I figured as much... ah well, the money pit deepens more :o

[xlr8nflorida]

Yep, I figured as much... ah well, the money pit deepens more :o

Go for it ! No fear headers not made in china :cheers:

[VetteMed]

:sign10: Yeah, that's a good point! Guess I can't say no, then.

Go for it ! No fear headers not made in china :cheers:

[tf95ZR1]

I have heard tales of cat substrate (or inner header coatings?) being
sucked back into the chambers. Urban myth?

[xlr8nflorida]

I have heard tales of cat substrate (or inner header coatings?) being
sucked back into the chambers. Urban myth?

I guess it could happen especially on deceleration.

I would just hack those babies off all together or get a test pipe or spend the $$$ for the headers :cheers:

[USAFPILOT]

Take it to Cory H's and put it on the dyno like Rhipsher did and let him blow the loose crap out! Rhipshers dented the door in Corey's garage when the cat materiel shot out like a cannon.

[tomtom72]

I have heard tales of cat substrate (or inner header coatings?) being
sucked back into the chambers. Urban myth?

I remember reading over at Marc's site about that being a distinct possibility. It happens during compression breaking. Marc said that exhaust reversion sucks the small fragments back up thru any exhaust valves that may be open......that can't be a good thing! Ouch!

The Fed's should grant all ZR-1's a waiver to use headers so we can avoid damage to our motors.....:o