Check your cats...

[Big Daddy Kane]

Well, I got my gutted cats back on. The car sounds a bit louder, but not much. It does sound good....I think so anyways. It is stinky though. Lol.

[MarylandSpeed]

Originally Posted by calbert1999

Bottom line manufacturers making shitty cats that don't hold up. Simple and plain.

I would not say that. A cat failing is the effect of a cause. I sell a lot of Kooks headers and have had less than a handful of customers contact me with melted cats and most were supercharged. However the more power you add, the more likely stuff will fail, just like axles, transmissions, and even engines. Cats are very sensitive to proper tuning at high HP levels. It is that simple.

[Blue70SS]

Originally Posted by MarylandSpeed

I would not say that. A cat failing is the effect of a cause. I sell a lot of Kooks headers and have had less than a handful of customers contact me with melted cats and most were supercharged. However the more power you add, the more likely stuff will fail, just like axles, transmissions, and even engines. Cats are very sensitive to proper tuning at high HP levels. It is that simple.

No disrespect, but I've heard of plenty of cats failing by several extremely reputable tuners here on C5. LT headers and Hi-flows just don't mix north of 600 RWHP IMO and researching. (even shortys with high flow cats have failed) I think a "perfect tune" that doesn't risk possible detonation or cat damage for the long haul at much higher RWHP is not obtainable. If emmision testing is a concern, the cats need to be installed for testing and keep a light throttle, then removed till next testing time. Every hi-flow cat manufacturer's excuse has been "poor tuning". Two high end cat manufacturers both reccomended this to me.

[Big Daddy Kane]

I shot a video of me backing the car into the garage with the gutted cats. Video isn't really exciting, but kinda gives you an idea what it sounds like.

[MarylandSpeed]

Again..I really think this assesment is wrong. It's not like putting cats on a supercharged car, they are going to instantly fail. Otherwise how do you explain that I have two supercharged cars, and one has had cats for 3 years, the other one, and they are both fine. Both also spend a lot more time racing and on the dyno than a normal car. I have nothing to gain here..if cats normally failed, I would tell people not to buy them, because I would rather not deal with upset customers when they do fail. However every warranty issue, Kooks contacts us to verify that the customer bought from us. And that alone tells me this is a much rarer situatation than this thread leads on. Just because you hear chatter on the internet does not mean that it is a gaurenteed outcome. The bottom line here is, if you supercharge your car..yes, there is a greater chance the cats can fail. Just like any other part can fail at a higher application. However properly tuned, a cat can last just fine.

Kooks uses the same cats on every other LSx application including LS3 Corvettes, and this is not an issue anywhere really but here. So there is either something going on in how these specific cars are designed or how they are being tuned.

As for tuners..they are an interesting group. I have personally talked to several reputable tuners, and when you mention another reputable tuner, it always.."Yeah, I have fixed a bunch of cars he tuned, or "That guy has no clue what he is doing". This will be one reputatable tuner talking about another. I have never dealt with a tuner that will say another tuner is better than him, or that someone elses tunes are as good as he could do. I strongly suggest everyone here to watch a Greg Brandish DVD one day. They cost alot, but they explain alot about the different ways of tuning a car. The first thing you learn is that there are plenty of ways to run a car, make it run okay, but still have it be a fairly lazy tune that does not address alot of things. Most customers would never know because tuning is largely a black science unless you are into it.


My comments are not aimed at anyone in particular in this thread. I just hate this conversation because any cat manufactuer will also tell you that cats don't just fail..there is a reason they fail..and it is normally the tune. Cats are made of the same material..and have very little variance in production. One tune to another can be 180 degrees different even though both cars run fine.

Originally Posted by Blue70SS

No disrespect, but I've heard of plenty of cats failing by several extremely reputable tuners here on C5. LT headers and Hi-flows just don't mix north of 600 RWHP IMO and researching. (even shortys with high flow cats have failed) I think a "perfect tune" that doesn't risk possible detonation or cat damage for the long haul at much higher RWHP is not obtainable. If emmision testing is a concern, the cats need to be installed for testing and keep a light throttle, then removed till next testing time. Every hi-flow cat manufacturer's excuse has been "poor tuning". Two high end cat manufacturers both reccomended this to me.

[JANNETTYRACING]

Originally Posted by MarylandSpeed

Again..I really think this assesment is wrong. It's not like putting cats on a supercharged car, they are going to instantly fail. Otherwise how do you explain that I have two supercharged cars, and one has had cats for 3 years, the other one, and they are both fine. Both also spend a lot more time racing and on the dyno than a normal car. I have nothing to gain here..if cats normally failed, I would tell people not to buy them, because I would rather not deal with upset customers when they do fail. However every warranty issue, Kooks contacts us to verify that the customer bought from us. And that alone tells me this is a much rarer situatation than this thread leads on. Just because you hear chatter on the internet does not mean that it is a gaurenteed outcome. The bottom line here is, if you supercharge your car..yes, there is a greater chance the cats can fail. Just like any other part can fail at a higher application. However properly tuned, a cat can last just fine.

Kooks uses the same cats on every other LSx application including LS3 Corvettes, and this is not an issue anywhere really but here. So there is either something going on in how these specific cars are designed or how they are being tuned.

As for tuners..they are an interesting group. I have personally talked to several reputable tuners, and when you mention another reputable tuner, it always.."Yeah, I have fixed a bunch of cars he tuned, or "That guy has no clue what he is doing". This will be one reputatable tuner talking about another. I have never dealt with a tuner that will say another tuner is better than him, or that someone elses tunes are as good as he could do. I strongly suggest everyone here to watch a Greg Brandish DVD one day. They cost alot, but they explain alot about the different ways of tuning a car. The first thing you learn is that there are plenty of ways to run a car, make it run okay, but still have it be a fairly lazy tune that does not address alot of things. Most customers would never know because tuning is largely a black science unless you are into it.


My comments are not aimed at anyone in particular in this thread. I just hate this conversation because any cat manufactuer will also tell you that cats don't just fail..there is a reason they fail..and it is normally the tune. Cats are made of the same material..and have very little variance in production. One tune to another can be 180 degrees different even though both cars run fine.

I have to disagree with your assessment, As a Tuner with 30 years experience and Last year Had an Advanced Training Class with Greg Bannish, that it is NOT always in the Tune, We covered this extensively in my Class.

If you put 10 lbs. of crap in a 5 lb. bag it is going to break.

The currently available cats can NOT handle the Exhaust Gasses from a supercharged 6.2 liter Engine

Put 10 Liters of Air through a 6 Liter Hole and it is going to over heat, melt and fail which if left unchecked will Fail a Piston in the engine.

Ted.

[Big Daddy Kane]

I'm just gonna throw my 2 cents in. My cats were ok when I checked them. But I only put about 500 miles on the car with the supercharger. I've read on here a year ago about cats failing with superchargers. It was something that stuck in my head because I knew one day that I would be going the FI route. Every tuner is different. And I made sure that I went with one that seemed to get the most positive feedback on here.

So when he sent my tune and suggested that I may want to get off road pipes because of the known issues with cats and superchargers, it made me more concerned. But I was still just gonna wait and see. There has been way more reported failures on here than there has non failures. So for mainly piece of mind, I went with the majority and my tuners suggestion, and got rid of the cats.

[Blue70SS]

Originally Posted by JANNETTYRACING

I have to disagree with your assessment, As a Tuner with 30 years experience and Last year Had an Advanced Training Class with Greg Bannish, that it is NOT always in the Tune, We covered this extensively in my Class.

If you put 10 lbs. of crap in a 5 lb. bag it is going to break.

The currently available cats can NOT handle the Exhaust Gasses from a supercharged 6.2 liter Engine

Put 10 Liters of Air through a 6 Liter Hole and it is going to over heat, melt and fail which if left unchecked will Fail a Piston in the engine.

Ted.

Well said Ted.... Besides, if it's a really high chance of cat failure and possible consequences - why risk the engine. Even more so for stock internals.

[calbert1999]

Originally Posted by Blue70SS

No disrespect, but I've heard of plenty of cats failing by several extremely reputable tuners here on C5. LT headers and Hi-flows just don't mix north of 600 RWHP IMO and researching. (even shortys with high flow cats have failed) I think a "perfect tune" that doesn't risk possible detonation or cat damage for the long haul at much higher RWHP is not obtainable. If emmision testing is a concern, the cats need to be installed for testing and keep a light throttle, then removed till next testing time. Every hi-flow cat manufacturer's excuse has been "poor tuning". Two high end cat manufacturers both reccomended this to me.

Well said;

I kind of gave up on responding to this same sorry excuse "bad tuning".

Too much finger pointing in the auto industry. Manufacturers / vendors need to take responsibility for their actions just like the consumer has to when shit screws up and it costs them money to resolve. When things go well everyone's ready to take credit, when they don't everyone starts pointing fingers.

Test and QA the CATS at varying power levels, it they don't hold up, just make different offereings for different requirements and charge accordingly giving shops and consumers different offerings. Some, will pay, some won't. Simple, honest approach to doing "good" business.

[madmaxx18]

[oachalon]

Originally Posted by S3XPanther

If you gut your existing hi flows you would have mid pipes that look like cats, but there's obviously nothing in there any more.

The problem is i currently have my stock exhaust, and a brand new set of solo high flow cats. The solo's will not bolt onto a set of LT headers, so i am going to sell them.

That leaves me with spending $200 on high flow cats and gutting them. I was hoping to find someone that sells headers with midpipes that look like cats.

[TCAT]

Would having high flow cats have a more difficult time holding up on a supercharged car or a turbocharged car? I wonder if it would make any difference as both are making boost, but in different fashions, and temps could be different between applications.

[Blacknight11]

Originally Posted by JANNETTYRACING

I have to disagree with your assessment, As a Tuner with 30 years experience and Last year Had an Advanced Training Class with Greg Bannish, that it is NOT always in the Tune, We covered this extensively in my Class.

If you put 10 lbs. of crap in a 5 lb. bag it is going to break.

The currently available cats can NOT handle the Exhaust Gasses from a supercharged 6.2 liter Engine

Put 10 Liters of Air through a 6 Liter Hole and it is going to over heat, melt and fail which if left unchecked will Fail a Piston in the engine.

Ted.

So Ted, i do not want to gut the cats (smell and more noise) so If I go back to stock with everything except the cat back kooks exhaust should I be ok? I think earlier you stated the stock cats will hold up to the SC. Im staying below 550 rear wheel. I still want to get the 3.6 pulley from you and tune will
that 3.6 pulley work with the stock items .

[blufin]

I didn't find out about this issue until after I ordered my exhaust/headers/SC last week. Looks like I'll be gutting my Kooks HF cats just to be on the safe side. And it will retain the appearance of having a cat, just in case.