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robmustang201528

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Had my blower on less then a week. I've been getting on since I've had it but i wasn't expecting my cats to fail that fast. I have highflow ARH cats. Turned up the boost to 12lbs, made a couple pulls felt pretty good. On my way home leaving the shop, made a pull in 2nd switched to third and the car bogged, check engine light blinked a couple times and went off. Got off the next exit and drove it back to the shop. Cylinder 8 misfire code popped up on the scanner. He cleared the code, ran a couple test everything checked out fine but the car didn't have the same sound that I'm used to hearing. Took it back to shop. Took the exhaust down and noticed the driver side cats were 50% clogged. Cut the old cats out and welded some 3in stainless steel pipe in its place. Mechanic said I don't need a retune so I should be good to go. Moral of the story is get rid of your cats if you have a supercharger. I hope I didn't mess anything up
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Crackerjack17

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That's a failure on the way those cats were constructed. That kind of failure is what the kook/gesi green cats are supposed to avoid.

 

venumous

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Ive been planning on taking mine off to check them. Ive never had an issue.
 

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venumous

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stang17

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I melted the stock cats on the Whipple tune at about 7,000 ish miles. I chalked it up to the dealer never gapping the NGK plugs that came with the kit.

I went ahead and put on Kooks 1 7/8 headers with their standard high-flow cats. Not even a few hundred miles later and the cats were starting to fail.

I called Kooks and was advised the only cats that "may" hold up to supercharged/turbo high horse power applications are the GESI green cats.

We just ended up removing all of the plugged up material and run hollow cats. No more sulfur smell and the car runs noticeably better. The Whipple tune adapted fine for no cats and my tuner only needed to make minimal changes such as rear 02 sensors CEL.

I'm fortunate enough to live close to enough work where I put less than 5,000 miles per year on the car and am emissions exempt.

Only drawback to not having the cats is the car got a bit raspy over 3,000 rpms. I'm trying to figure out how to get that low bass rumble I had prior with the magnaflow comp cat back and stock manifolds/cats.
 

Performance nut

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You can keep them, just have to tune differently. To each their own though. I rather tune with some on.
 

Boduke0220

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I melted the stock cats on the Whipple tune at about 7,000 ish miles. I chalked it up to the dealer never gapping the NGK plugs that came with the kit.

I went ahead and put on Kooks 1 7/8 headers with their standard high-flow cats. Not even a few hundred miles later and the cats were starting to fail.

I called Kooks and was advised the only cats that "may" hold up to supercharged/turbo high horse power applications are the GESI green cats.

We just ended up removing all of the plugged up material and run hollow cats. No more sulfur smell and the car runs noticeably better. The Whipple tune adapted fine for no cats and my tuner only needed to make minimal changes such as rear 02 sensors CEL.

I'm fortunate enough to live close to enough work where I put less than 5,000 miles per year on the car and am emissions exempt.

Only drawback to not having the cats is the car got a bit raspy over 3,000 rpms. I'm trying to figure out how to get that low bass rumble I had prior with the magnaflow comp cat back and stock manifolds/cats.
GT500 takeoff mufflers work very well
 

AdrianMAK

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We have seen that happen more than a few times with boosted applications. Just the nature of it, the Green Cats are supposed to handle boost although we haven't tested those ourselves. Some cats live and some don't. I will tell you that if the above picture happens and it plugs up the exhaust, the result is not going to be pretty.

We understand some guys have no choice, but the best cat is no cat when it comes to making power.
 

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robmustang201528

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Now I have a cylinder 8 misfire code f##%#$ SMh. I hop I just missed up the plug. The car is still responsive. Drives normal, no weird sounds. Came on a gain when I was getting on it
 
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robmustang201528

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I hope I didn't mess up the engine. Going into panic mode right now smh
 

F1scamp

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Well now the question in my mind is did the misfires cause the cat destruction, or did the cat destruction cause the misfires. Its weird that the misfires are on both sides of the motor. Did both cat's fail? I would definitely stop driving it until you at the very least pull the plugs and see if anything obvious is going on. Good luck man, shit like this sucks.
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