Check your cats...

[bluetorp]

Duty cycle/loading is definitely a big factor. The cats that fried at 400 RWHP NA that I referred to above came out of a car that was mostly used for running road courses.

I want to quote out the below specifically:

Originally Posted by JANNETTYRACING

I agree with your assessment to a point, We have seen 3-5 sets of cats fail (all from guys who either Race or Use the Power Alot) out of the several hundred we have sold installed and tuned and that is enough to cause concern.

Maybe the disconnect with some of us is simply what failure threshold is a cause for concern? If I assume several hundred = 300, than with your numbers quoted above it represents a 1-1.6% failure rate. Considering the fact that we're talking about significantly modified engines being subjected to rigorous use, a certain potential for part failure comes with the territory. I'd actually consider a cat failure rate of 1-1.6% to be really good, all things considered. Not statistically insignificant, but not high enough to deter someone from putting cats on their +600 RWHP supercharged motor if they feel they need to for emissions/smell/sound/whatever.

[Caliman93230]

Can some make HD high flow cats that will last longer ?

[69 Rebel]

Let's all agree to disagree on why cats fail. The fact still remains they are failing. We need a solution, the people making the cats should do some R&D and find out exactly why they are failing and come up with a cat for high HP cars period. We obviously need them for emmissions, noise ,smell etc. and there is obviously a market for it.

[bluetorp]

I think you're missing the point that some of us are trying to make. No one is questioning that sometimes cats fail. They fail on NA cars making less power as well as FI cars making +600 RWHP. We basically agree on what causes cats to fail. What we disagree on is that these isolated failures are anything but isolated failures, and that they represent a core design insufficiency. Taking the sample numbers posted by Ted, you have approximately a 1 in 100 chance of melting an aftermarket high flow cat (question for Ted: are those numbers inclusive of all modded cars you've done that have cats, or just the supercharged ones?). That's not a figure that an aftermarket cat manufacturer is going to look at and decide that they have to do a redesign, I'm sorry to say.

We're not treading any new ground here. We're not pushing these parts to previously un-reached levels of power. If cat failure is such a big problem, why is Camaro5 the only place you'll find an 8-page crisis thread about it? I couldn't find anything similar on LS1Tech, and I have yet to see anything like this on any other LSx forum. People have been meeting and exceeding these power levels on LS motors, using these same parts, for years, and trust me- if cats were melting off of everyone's +600 HP supercharged motors, there would damn well be EPIC threads about it on LS1Tech. A single run of TSP ported Dart heads that had oil burning issues (I seem to recall that the problem was the Dart valve stem seals, and not TSP's) generated a 10-page thread over there, so believe me when I tell you that if there was a problem with mass cat failures on FI motors, we would have heard about it by now.

[69 Rebel]

So what your saying is that the C5 members have a mob mentality Don't get me wrong you sound like you know your stuff. I think there was a post here where the guy found a few more pages on the subject, so this is not new.

If i didn't have Hi Flow cats and read this thread, knowing my chances are 1 in 100 that i melt them with my FI car, i wouldn't take those odds, and just get mid pipes

[572HP]

Originally Posted by bluetorp

On an interesting note: My HPT finally got out here to the desert today. I hooked it up and pulled the canned tune from Whipple off the PCM so I could take a look and start modifying.

COT protection is DISABLED in the canned tune from Whipple.

I think that this is a VERY important statement. If true (I'm not saying that it isn't, but I can't confirm), and what Ted has told me personally, as well as what I was told personally from ARH, then what I am lead to believe is that there are several factors coming into play here. If you have FI, cats, and if COT protection is disabled, then there doesn't sound like there is anything in there trying to protect the CATS. Doubling the size of the cats, or removing the cats...sure that will fix it. However, I believe that a tuner that knows about cat thermal management has a good chance at eliminating the issue.

If a tuner that knows about the thermal management was able to look at the tune on a vehicle with burned cats, he may find that the tune was to blame. Blindly turning off COT protection on a FI car, and assuming that the user is not using cats, is being negligent unless they state that the FI should not be used with cats.

I for one, plan to run with cats. I will make sure that I trust my tuner, and verify that they have taken into account that I am using cats. I will also keep an eye on the cats. I also may remove the cats when I head to the track. Ted says that he can create one tune file for cats, and one without, so that I can swap between the two. I'm sure everyone is not willing to go to that level. However, I am not willing to run without cats on the street like some of you.

This is obviously a very complex issue. Learning about this issue is a must for guys that call themselves tuners. It is helpful for us to be able to choose a tuner to trust.

Ted, you have stated on here that the issue is related to the volume of air, and not the fault of a tune. Don't you agree that if COT protection is disabled in the tune, that it could contribute to the cause of the cats melting?

[bluetorp]

I'd say that humans in general have a mob mentality. But no, I'm not trying to make any veiled insinuations against Camaro5 forum posters.

I think the discussion is great, people just need to understand that there's a counterpoint. If I'm Joe Anybody, and this is the forum I come to to get technical info about my car, when I see this thread I'm going to think that cats are failing all the time on supercharged motors, and that isn't the case. Now that we're 8 pages in, we have a rough estimate of failures that Ted has seen. It seems to jibe with the failures MarylandSpeed has seen as well. Namely, out of all the catted supercharger installs they have done, there have been a mere handful of failures.

Nobody is saying that failures aren't happening, or that they are not more common in FI setups. That's pretty widely accepted. However, it's not a pervasive enough issue that anyone should be running out to gut their cats. The chances of a cat failing are very small, aside from an external causality such as a lean tune producing abnormally high EGTs, for example.

[bluetorp]

I was very surprised to see that COT protection was disabled. The rest of the tune looks very safe and conservative.

While they were in there turning off COT protection, they could have at least killed CAGS and DFCO as well.

[572HP]

Originally Posted by bluetorp

I was very surprised to see that COT protection was disabled. The rest of the tune looks very safe and conservative.

While they were in there turning off COT protection, they could have at least killed CAGS and DFCO as well.

Off topic...but I for one love DFCO. I like a little pop in the exhaust on deceleration and the benefit of better gas mileage. As for CAGS...I agree. Nothing but annoying for the end user. I had to google these terms. Not very well versed on tuning.

[JANNETTYRACING]

Originally Posted by 572HP

I think that this is a VERY important statement. If true (I'm not saying that it isn't, but I can't confirm), and what Ted has told me personally, as well as what I was told personally from ARH, then what I am lead to believe is that there are several factors coming into play here. If you have FI, cats, and if COT protection is disabled, then there doesn't sound like there is anything in there trying to protect the CATS. Doubling the size of the cats, or removing the cats...sure that will fix it. However, I believe that a tuner that knows about cat thermal management has a good chance at eliminating the issue.

If a tuner that knows about the thermal management was able to look at the tune on a vehicle with burned cats, he may find that the tune was to blame. Blindly turning off COT protection on a FI car, and assuming that the user is not using cats, is being negligent unless they state that the FI should not be used with cats.

I for one, plan to run with cats. I will make sure that I trust my tuner, and verify that they have taken into account that I am using cats. I will also keep an eye on the cats. I also may remove the cats when I head to the track. Ted says that he can create one tune file for cats, and one without, so that I can swap between the two. I'm sure everyone is not willing to go to that level. However, I am not willing to run without cats on the street like some of you.

This is obviously a very complex issue. Learning about this issue is a must for guys that call themselves tuners. It is helpful for us to be able to choose a tuner to trust.

Ted, you have stated on here that the issue is related to the volume of air, and not the fault of a tune. Don't you agree that if COT protection is disabled in the tune, that it could contribute to the cause of the cats melting?

Absolutely, As I stated above I don't turn it off in cars with cats.

[Caliman93230]

Bluetrop I don't think people want to take the risk or be that one in 100 that had a cat failure and blew the engine, are you a manufacture of high flow cats? do you sell them.

[Blue70SS]

Originally Posted by mike25

There are so many variables, as clearly stated in this thread, that you cant say cat failure is guaranteed with a supercharger..you have different parts, different tunes, different temperatures humidity elevation etc that play into the way a car runs etc. Is it "wise to run without cats? the answer is an obvious yes.

Theres a potential for cat failure, "wise" indicates your not oblivious to this and take the steps to prevent it. However, it isnt "wise" just state if you have a car with 600+hp on forced induction that its automatically going to fail...

Good points, well recieved and respected..... Just to be clear, I don't think anyone said superchargers are guaranteed failure or 600+hp on FI is automatic failure.

Higher potential for cat failure at higher boosted HP levels and harder to tune for should be the message. It's good to know that the tune can be the cause and tuners could be turning off cat protection, etc, etc. Those wanting to run cats under these conditions will now be better educated and hopefully wiser.

On another note (to all)... I called a cat manufacturer (to remain nameless for sake of argument not needed), and they thought cat failures on higher boosted engines was primarily happening not during boost, but on deceleration, but can be properly tuned. I asked what properly tuned was, in particular if they were finding too rich or too lean affected it more so. Response was, "it can be tuned for". A more helpfull "note to tuners: parameters that work best on our cats" sheet would be more helpful. "Tune" just seems to be the blanket statement still.

[Stark]

First chance i get, i'm gonna pull my Kooks HiFlow Cats and check them.
( pics will post in my build thread )
I'm i having problems ? No.
I have a good and trusted Tuner. ( John Lee @ APF )
But at 615, rwhp, it's worth the time and effort to check.
A 2.8 Kenne Bell at 7.5 boost is mild.
6k miles on S/C and Kooks L/T headers , cats exhaust.
But if a high temp exhaust shows a STRONG degree of melting the cats and
causing engine failure is more than just "rare" occurrence , exhaust companies owe us to R & D their "hi-flow" cats for not only N/A apps, but also FI apps as well.
My opinion? Yes.
If you sell a product for n/a applications, fine, Say so.
If you go above and beyond for F/I, you forge a path that people talk
about for years to come.

[MarylandSpeed]

Originally Posted by Caliman93230

Bluetrop I don't think people want to take the risk or be that one in 100 that had a cat failure and blew the engine.

This is the logic I don't get. Failed cat does not normall = blown engine. Sure your cat can fail..but the odds of a cat failing, and then blowing the engine are astronomical. Really you would have to ignore several OBVIOUS drivability issues for it to get to the point that it damaged the engine. I would say the odds of your cats failing, and then an owner ignorning the drivability issues long enough for the cat to fail are 1 in a million. OEM cats fail on normal every day cars all the time, and I have never heard of anyone blowing and engine from a cat failing. If you are giving yourself heart burn over this issue then you really should not have a supercharged car. There are plenty of catastropic things far more likely to happen simply from supercharging the car.