Question for guys who actually have the the Roush Kit

Navymike

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Just remove the cats 🤫. I actually have mid pipes with no cats and a set of $1400 GESI cats if the day comes that I need to ever run cats
 

tosha

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Just remove the cats . I actually have mid pipes with no cats and a set of $1400 GESI cats if the day comes that I need to ever run cats
Link to midpipes? Is there some sort of exensions that go instead of cats? I assume you can still use roush provided tune? Thanks for the feedback.
 

Navymike

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Link to midpipes? Is there some sort of exensions that go instead of cats? I assume you can still use roush provided tune? Thanks for the feedback.
Oh sorry I have long tubes that requires a return. I’m not sure if you just deleted the cats and left the manifold if you would need a retune. I think cat protection would still be on. But that make a cat delete kit for stock manifold
 

Hadelson

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A big reason I got rid of my 19 Roush Stage 3 running the Phase 2 calibration was too many P0420/P0430 cat codes and had 3 cats replaced on the drivers side and 2 on the passenger side. That’s ridiculous.
Sitting at 10, 500. Getting ready to upgrade to Roush Max Colling system and latest calibration. Car is garaged for the next two month. Hoping I don't see this once I start driving again late March.

Edit: 1/16. I am going to have the Dealer run Cat Diagnostics when they install latest Roush Calibration.
 
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Lunchabull

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If i didn't live in NY with the dumb emissions test we have every year my cats would be long gone.
 

Steve68Cougar

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I got the code for a malfunctioning catalyst converter today, so will make an appointment to take it in and have it replaced.
I'm needing to get mine in and get cat #2 and #3 replaced. I'm definitely looking at doing something different with the exhaust once I have the new cats installed. I'm at about 22k miles. Makes an otherwise fun ride be a bit frustrating.
 

m3incorp

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Appointments are month or two out here to get them to diagnose and then order the part. The kicker is, I am no where near the mileage but only a month away from the 36 months. They supposedly have a new software download that reduces the cat temps in certain instances and prolongs the life. If I had to pay on my dime, I would probably install high flow cats and be done with it.
 

engineermike

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The stock gt cat honeycomb “tendons” are sooo thin and delicate. The gt500 cats are 1/3 the cell count and the tendons are 2-3x thicker. I think that thermal shock is what’s taking them out. During rapid heat up, the thermal expansion isn’t even across the monolithic block so thermal stresses increase and break the tendons.
 

Steve68Cougar

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Appointments are month or two out here to get them to diagnose and then order the part. The kicker is, I am no where near the mileage but only a month away from the 36 months. They supposedly have a new software download that reduces the cat temps in certain instances and prolongs the life. If I had to pay on my dime, I would probably install high flow cats and be done with it.
Emissions equipment is warranted fo 5 years and 80k miles if I remember right. My 3/36 is just about up, too. I think appointments are about 6 weeks out at the dealership I go to.
 

Steve68Cougar

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The stock gt cat honeycomb “tendons” are sooo thin and delicate. The gt500 cats are 1/3 the cell count and the tendons are 2-3x thicker. I think that thermal shock is what’s taking them out. During rapid heat up, the thermal expansion isn’t even across the monolithic block so thermal stresses increase and break the tendons.
Any chance the GT500 stuff will work on my '18?
 

engineermike

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Any chance the GT500 stuff will work on my '18?
Not super easily. I have gt500 cats on my 2018, but it required a fair amount of fitting and welding.

Passengers side will bolt up to the stock manifold using a spacer but the other end is bigger. Drivers side is more involved.
 

Steve68Cougar

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Not super easily. I have gt500 cats on my 2018, but it required a fair amount of fitting and welding.

Passengers side will bolt up to the stock manifold using a spacer but the other end is bigger. Drivers side is more involved.
Once the fab work is done, is there any tuning that needs to be done? I'm not scared of a little fab work if it lets me keep the tune. Any down sides?
 

engineermike

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Once the fab work is done, is there any tuning that needs to be done? I'm not scared of a little fab work if it lets me keep the tune. Any down sides?
No, not at all. I’ve logged several cat test cycles and the gt500 cats prevent rear o2 switching nearly as good as stock. They are a little louder than stock.

More info for DIY fabricators….

Passengers side will bolt to the stock manifold but the expansion joint is up against the floor pan heat shield. A 3/8” spacer gets a little clearance. The stock studs are marginal length for this, which is the only thing I dont like so far. The spacer can be purchased off eBay or Amazon.

Drivers side gt500 has a 2-bolt flange like the passengers side, but stock is all one piece with no flange. Gen 1 used a flange here but the orientation is wrong. Gt500 headers won’t bolt to your head so that only leaves one option: cut the stock manifold and weld on a 2-bolt 3” flange. The good news is that the drivers side manifold is actually pretty easy to remove.

Once the above is done, you’re left with 2.75” pipes where the stock “factory connect” is only 2.25”. You’ll have to choose what you want to do from there back because the stock resonator is only 2.25” iirc.
 

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That is usually true but don't know if that is still true with the Roush Supercharger added. My preferred dealership doesn't have an appointment until late May. I am checking everywhere within 3-4 hours so, I don't have to deal with it possibly not being honored because of the supercharger and 36 months. Tinder Ford is about 3 hours out and supposed to call me back tomorrow. The kicker is no most dealers don't stock the cats and will have you come in for diagnostics before they will order....so two trips at least. I guess I will be polluting the air for a while on the weekends.

Emissions equipment is warranted fo 5 years and 80k miles if I remember right. My 3/36 is just about up, too. I think appointments are about 6 weeks out at the dealership I go to.
 

Lunchabull

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That is usually true but don't know if that is still true with the Roush Supercharger added. My preferred dealership doesn't have an appointment until late May. I am checking everywhere within 3-4 hours so, I don't have to deal with it possibly not being honored because of the supercharger and 36 months. Tinder Ford is about 3 hours out and supposed to call me back tomorrow. The kicker is no most dealers don't stock the cats and will have you come in for diagnostics before they will order....so two trips at least. I guess I will be polluting the air for a while on the weekends.
When mine went earlier this year I was told by the Dealer that it was a 7 year warranty and the supercharger addition didn't matter. They replaced it no problem, dropped the car off on Wednesday for diagnostics and picked it up the following Monday.
 
 
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