Blowing cats out?
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,823
Likes: 42
From: East Aurora NY
Blowing cats out?
I have a 02 Z06 with worked heads and a cam with some decent overlap. Dyno tuned, AFR is fine while driving and @ WOT.
This winter I noticed some sparkly flakes in my exhaust, they are not solid like small pieces of metal but more like compressed power (if that makes any sense).
I didn't expect the XS Power cats to last long, but does it appear I am in the right direction? Axle back is borla stingers.
This winter I noticed some sparkly flakes in my exhaust, they are not solid like small pieces of metal but more like compressed power (if that makes any sense).
I didn't expect the XS Power cats to last long, but does it appear I am in the right direction? Axle back is borla stingers.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
What kind of CATs do you have (STOCK or AFTERMARKET) and how old are they?
Are they working? Use an inferred laser pointer temp sensor and see if the outlets are heating up 300 deg hotter than the CAT inlet temp.
If you hit the cats with a rubber mallet, do you hear rattleing nouses?
BC
Are they working? Use an inferred laser pointer temp sensor and see if the outlets are heating up 300 deg hotter than the CAT inlet temp.
If you hit the cats with a rubber mallet, do you hear rattleing nouses?
BC
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,823
Likes: 42
From: East Aurora NY
Close loop part throttle cruise in the 14s, generally mid 14.3-14.5s
LTFT's < 2%
Aftermarket cats, the ones that come with the XSPower headers, lower cell count? About 3 years old, learned to tune with them in place at I'll be honest it was running rich for a bit.
10* overlap on the camshaft
Don't have a laser temp gauge, I'll try to pick one up soon.
Gave them a tap with a rubber mallet, no rattling but they didn't sound like they had much in them. Then again I've never hit cats before with a rubber mallet
LTFT's < 2%
Aftermarket cats, the ones that come with the XSPower headers, lower cell count? About 3 years old, learned to tune with them in place at I'll be honest it was running rich for a bit.
10* overlap on the camshaft
Don't have a laser temp gauge, I'll try to pick one up soon.
Gave them a tap with a rubber mallet, no rattling but they didn't sound like they had much in them. Then again I've never hit cats before with a rubber mallet
Melting Slicks
Joined: May 2008
Posts: 2,606
Likes: 355
From: Rochester New York
Who performed your tune? Was it tuned with a wideband? Do you currently run a wideband and an EQR gauge? What fuel are you using? Any changes to the car after the tune? How long were you running rich for? How many miles are on your stock narrowbands?
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,823
Likes: 42
From: East Aurora NY
I tuned the car myself and yes it was with a wideband (NGK with upgraded sensor)
Running 93 pump and no changes to car after tune. I was running rich at part throttle for a few hundred miles. Rich being in the 13s AFR wise (part throttle cruise).
Tune is fine now
Miles on the narrowbands was less 4000 as I replaced them last winter.
Running 93 pump and no changes to car after tune. I was running rich at part throttle for a few hundred miles. Rich being in the 13s AFR wise (part throttle cruise).
Tune is fine now
Miles on the narrowbands was less 4000 as I replaced them last winter.
Melting Slicks
Joined: May 2008
Posts: 2,606
Likes: 355
From: Rochester New York
I tuned the car myself and yes it was with a wideband (NGK with upgraded sensor)
Running 93 pump and no changes to car after tune. I was running rich at part throttle for a few hundred miles. Rich being in the 13s AFR wise (part throttle cruise).
Tune is fine now
Miles on the narrowbands was less 4000 as I replaced them last winter.
Running 93 pump and no changes to car after tune. I was running rich at part throttle for a few hundred miles. Rich being in the 13s AFR wise (part throttle cruise).
Tune is fine now
Miles on the narrowbands was less 4000 as I replaced them last winter.
I'll assume the tune is correct and you are not running too lean or rich. The XS power cats aren't the best to begin with. It's possible they've crapped the bed. I'm not sure on how cats react with big cams, but I doubt they heat up properly which can be detrimental as well.
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Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,823
Likes: 42
From: East Aurora NY
I was thinking those cats are not the best to begin with anyway, plus add in the overlap of the cam and I doubt they are getting the best env for them.
I will be throwing the car on a loaded mustang dyno this spring and plan on checking everything over.
If the cats are breaking up, I worry they might clog the muffler if the chunk is large enough. Borla stingers should be straight through. Wondering if I should just gut them (the cats).
I will be throwing the car on a loaded mustang dyno this spring and plan on checking everything over.
If the cats are breaking up, I worry they might clog the muffler if the chunk is large enough. Borla stingers should be straight through. Wondering if I should just gut them (the cats).
Pro
Joined: Apr 2010
Posts: 651
Likes: 17
From: MD
my car was bone stock and I blew a huge chunk off the cats.. didnt know it until i removed the cats to install headers 
and that chunk, I have no idea where it went.. it isn't in the muffler because I have no mufflers with SLP loudmouth. 
and that chunk, I have no idea where it went.. it isn't in the muffler because I have no mufflers with SLP loudmouth.
Melting Slicks
Joined: May 2007
Posts: 2,014
Likes: 48
From: Dayton Ohio
Blew out my stock cats after my Procharger. Do like the sound better now 
Started out as a nice little white dust on the inside of the tips after a drive and it put on a nice smoke show of cat particles when under full throttle then they rattled and I beat them out
Started out as a nice little white dust on the inside of the tips after a drive and it put on a nice smoke show of cat particles when under full throttle then they rattled and I beat them out
Melting Slicks
Joined: May 2008
Posts: 2,606
Likes: 355
From: Rochester New York
I was thinking those cats are not the best to begin with anyway, plus add in the overlap of the cam and I doubt they are getting the best env for them.
I will be throwing the car on a loaded mustang dyno this spring and plan on checking everything over.
If the cats are breaking up, I worry they might clog the muffler if the chunk is large enough. Borla stingers should be straight through. Wondering if I should just gut them (the cats).
I will be throwing the car on a loaded mustang dyno this spring and plan on checking everything over.
If the cats are breaking up, I worry they might clog the muffler if the chunk is large enough. Borla stingers should be straight through. Wondering if I should just gut them (the cats).