[BMWM.D.]

There's a whole lot of factors that come into play. Like I said before, tuning is a big part of it. A lot of Corvette guys had issues trying to run cats on high compression supercharged pump gas combos. You can't run much timing with a setup like that, and most tune AFR for max power. A lot of tuners turn COT off as well. None of that is good for cat longevity.

I know the way I set up, tune, and drive my cars, good cats hold up. This includes half mile events, which is where I'd expect cat failure. Your results may vary.

[BSR-1]

Originally Posted by BMWM.D.

A lot of tuners turn COT off as well. None of that is good for cat longevity.

COT?

[RobZL1]

Originally Posted by BSR-1

COT?

Catalyst Over Temperature

It's a strategy in the tuning that basically dumps fuel to cool the cats when it thinks they are too hot. I believe it is based on a simple multiplier of the commanded AFR, but I may be wrong about that.

[DrkPhx]

Aftermarket cats won't melt because they're a metal substrate unlike the OEM which are ceramic; but they can collapse over time.

OP - If you want to install cats, save your money and stick with the regular high flow ones. I ran the Kooks green cats and they threw codes immediately after installation. Others had the same problem. Even though they were more of a nuisance code; it was still frustrating to spend the money and still have the codes. Eventually I ditched them after it was heavily modded and they started to collapse.

[cbourbs]

I have recently installed a roto fab intake, ported throttle body, and deleted my secondary cats in my 2019 ZL1 1LE. I was thinking of buying the kooks jet coated green cat headers and get a pulley and tune and call it a day.

After coming across this thread it scares me that the cats will gut themselves and I plan on circuit racing the car. I really like the sound of my car as is with the secondary cats deleted, and that's why I want the green cats for the headers. I don't like the raspy sound without the cats and the fuel smell isn't the best either.

So is a rich tune the solution and not disabling COT? I heard of people putting in 2 sets of resonators to get rid of the raspyness.

I just don't get the 600whp number....all the hypercars have lots more than that number, svj, 488, 720s, 812 etc...has to be the lean tuning...right?

[regnouy37]

DO NOT waste your money on Green Cats. Mine failed after some spirited runs through the mountains. I received a P0300 code with a Need Differential Service warning in the dash. I first thought I had an exhaust leak. However, when I got home, I had several pieces of the Green Cat pieces lodged in my exhaust. I ended up going with a Corsa x-pipe, which resulted in another 8 horsepower and 20 torque.

[cbourbs]

Originally Posted by regnouy37

DO NOT waste your money on Green Cats. Mine failed after some spirited runs through the mountains. I received a P0300 code with a Need Differential Service warning in the dash. I first thought I had an exhaust leak. However, when I got home, I had several pieces of the Green Cat pieces lodged in my exhaust. I ended up going with a Corsa x-pipe, which resulted in another 8 horsepower and 20 torque.

Was your car tuned and leaned out compared to the stock tune?

[regnouy37]

Originally Posted by cbourbs

Was your car tuned and leaned out compared to the stock tune?

Yes, car was and is tuned. It actually ran very well with the Green Cats until it was pushed a bit. Another ZL1 owner at the same shop I had my work done also swapped his Green Cats out once he saw what happened to mine.

[drfeelgood]

I'm running high flow cats with mine (non Green Cats), but my power level is pretty low. I'm just a tad bit over 600whp and never track it.

[regnouy37]

Originally Posted by drfeelgood

I'm running high flow cats with mine (non Green Cats), but my power level is pretty low. I'm just a tad bit over 600whp and never track it.

That's solid power. Be mindful if you ever decide to push your car for longer than 20 minute sessions. The cats may not be able to handle it. I first noticed what looked like foil in my muffler, and as I went upstream near the Green Cats, it got much worse.

[cbourbs]

Originally Posted by regnouy37

That's solid power. Be mindful if you ever decide to push your car for longer than 20 minute sessions. The cats may not be able to handle it. I first noticed what looked like foil in my muffler, and as I went upstream near the Green Cats, it got much worse.

Oh wow....that's crazy. I watched a video with them explaining how their cats work. They were saying how they put them through all this punishment and they can easily handle 1500 degrees...rather disappointing

I'm not a fan of the sound with no cats. I wonder how I keep it sounding like it does now with some extra added pops and snaps.

I just don't understand how all these factory cars with more horsepower than the zl1 don't have issues.

[drfeelgood]

Originally Posted by regnouy37

That's solid power. Be mindful if you ever decide to push your car for longer than 20 minute sessions. The cats may not be able to handle it. I first noticed what looked like foil in my muffler, and as I went upstream near the Green Cats, it got much worse.

Low power is relative, afterall I am in the ZL1 forum

I just wanted to pump and go, no flex fuel, no meth, etc. So my mild build is what was recommended by my tuner for my needs. But I agree 100%, I am likely at the upper limits of what my cats could take with continuous abuse...

thanks for sharing your experience. If I decided to go bigger power, the cats are coming off

[regnouy37]

Originally Posted by cbourbs

Oh wow....that's crazy. I watched a video with them explaining how their cats work. They were saying how they put them through all this punishment and they can easily handle 1500 degrees...rather disappointing

I'm not a fan of the sound with no cats. I wonder how I keep it sounding like it does now with some extra added pops and snaps.

I just don't understand how all these factory cars with more horsepower than the zl1 don't have issues.

I watched one of their Green Cat videos as well, and they had me sold on what the capabilities were supposed to be. I don’t abuse any of my vehicles, but I occasionally go on spirited runs in the hills near where I live. The day the cats failed I went on a 200 mile road trip with one other ZL1 (stock) and 10 or so Porsches. The cats failed about 120 miles into the trip. I limped home the last 80 with a partially clogged exhaust (right side).

Car is now slightly louder, but much more crisp with more pops and crackles.
Also, the car seems to breath better, hence the 8 hp gain and 20 tq.

[drfeelgood]

Originally Posted by regnouy37

I watched one of their Green Cat videos as well, and they had me sold on what the capabilities were supposed to be. I don’t abuse any of my vehicles, but I occasionally go on spirited runs in the hills near where I live. The day the cats failed I went on a 200 mile road trip with one other ZL1 (stock) and 10 or so Porsches. The cats failed about 120 miles into the trip. I limped home the last 80 with a partially clogged exhaust (right side).

Car is now slightly louder, but much more crisp with more pops and crackles.
Also, the car seems to breath better, hence the 8 hp gain and 20 tq.

what are you doing at the wheels? Mods?