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Catted long tube headers safe for boost?

ZXMustang

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What are we looking at for LTHs that are safe for boost? Kooks? Stainless works? Anyone have any experience with them yet?
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ZXMustang

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Thats not ideal. I took a blood vow with myself many years ago to never again own a car with no cats. I cant stand how awful the raw exhaust smells, plus the coyote becomes so ratty sounding with headers and no cats. Its just not on my playlist.
 

smurfslayer

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My tuner warned me that eventually they will fail under boost at a faster rate than a N/A car. I've lost 3(?) cats on n/a cars. 2 on one of my old Mustangs, Bassani x pipe and one on an old v6 Exploder. All 3 times the cat broke apart and caused a serious impact to power. The Exploder couldn't maintain 60mph uphill, wide open.

Now think about that happening during a 1/4 mile, track day or dyno pull under heavy boost.

Maybe the GT500 cats or Raptor R? But, the thing is, they tuned quite differently than we would be tuning.

I hear you about the rasp and overall loudness. Not my jam either. I had a car in my 20's that would set off car alarms, fun to drive around locally but not on trips longer than about 20 miles.
 

robvas

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My Kooks cats are still alive

I bought a set of off-road pipes from Kooks but put them back after a couple days. Waaaay too raspy.
 


Westphal

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GM somehow got their cats to last in their supercharged V8s, even running them on road race courses.
 

robvas

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GM somehow got their cats to last in their supercharged V8s, even running them on road race courses.
Because they were designed to be used like that. GT500 cats also last.

It's supercharging the NA cars which is the problem with the Mustang. The cats weren't meant to have double the exhaust flow going through them, along with higher temps.

The Camaros have 4 cats don't they?

edit: yes

S650 Mustang Catted long tube headers safe for boost? 2016-chevrolet-camaro-accessories-underbody-on-display-at-sema-photo-gallery_21
 

smurfslayer

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Yeah, we've had the discussion about the GT500 cats before, but I'll ask again - will they hold up to the stage 2+ whipple tune, or stage 2+ aftermarket (non-whipple) tune vs. say the stock eaton?
I'm asking.

I'd be ok with extra resonators to calm the sound, not wanting to surrender much any power
 
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ZXMustang

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My tuner warned me that eventually they will fail under boost at a faster rate than a N/A car. I've lost 3(?) cats on n/a cars. 2 on one of my old Mustangs, Bassani x pipe and one on an old v6 Exploder. All 3 times the cat broke apart and caused a serious impact to power. The Exploder couldn't maintain 60mph uphill, wide open.

Now think about that happening during a 1/4 mile, track day or dyno pull under heavy boost.

Maybe the GT500 cats or Raptor R? But, the thing is, they tuned quite differently than we would be tuning.

I hear you about the rasp and overall loudness. Not my jam either. I had a car in my 20's that would set off car alarms, fun to drive around locally but not on trips longer than about 20 miles.
I’m starting to get some white soot on my tips and some smoke under boost and the car is noticeably louder and smells bad at idle. I think mine failed or are in the process of failing. I have the ESS kit. Tuning on my own obv. It’s apparently clear the stock cats are a liability.
 

smurfslayer

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I’m starting to get some white soot on my tips and some smoke under boost and the car is noticeably louder and smells bad at idle. I think mine failed or are in the process of failing. I have the ESS kit. Tuning on my own obv. It’s apparently clear the stock cats are a liability.
For sure - at least half a dozen 7g reporters of melted cats post stage 1 whipple install.
 
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ZXMustang

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For sure - at least half a dozen 7g reporters of melted cats post stage 1 whipple install.
Are they seeing smoke under boost? That’s my current issue and I’m positive it’s cats melting in real time. Doesn’t feel down on power.
 

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No high flow Cats will hold up over Time . Kooks Green or GESI Gen 2 would be your best options
 

135Hoser

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I’m starting to get some white soot on my tips and some smoke under boost and the car is noticeably louder and smells bad at idle. I think mine failed or are in the process of failing. I have the ESS kit. Tuning on my own obv. It’s apparently clear the stock cats are a liability.
White soot on the tail pipe was my sign that the cat had failed.
 

smurfslayer

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No high flow Cats will hold up over Time . Kooks Green or GESI Gen 2 would be your best options
Do you have some measurable metrics here? # of drag passes on xxx blower using xxx tune, or number of track days, miles.

If you just commute to work, I'm sure they'll last unless your commute is truly impressive. Beyond that, I'm not certain and not willing to take the chance.
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