Secondary Cat Removal, Really Worth It?
#31
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Beg to differ but I am in NY, have the Fabspeed pipes and just had extensive work done at the dealer under CPO including a new transfer case and rear diff. The Porsche dealer could not have missed the pipes and said not a word. Similarly, I just had the truck inspected and it passed with flying colors...no reflash and no problems.
I'm just a messenger. I'm glad you had success, but clearly this techart dealer said multiple folks have not. He's also a dealer for tubi, akrapovik, etc. He claims to have this very conversation with folks 2-3 times a week, all certain they will pass because of what they read on the internet. He's an inspection shop for NY as well, and wasn't ambiguous at all, he's had multiple cayennes fail with the pipes installed. He's also had customers declined warranty repairs on any engine systems because of them.
I don't have a reason to doubt you, glad you passed and your dealer doesn't care. But I don't have a reason to doubt him either, so I'm thinking I'll just do a cat back exhuast and leave the cats alone. He was also clear, if you live in another state, emissions are probably not an issue. He was specifically talking NY (and implying California).
#32
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fpena,
I totally agree with the transformation of the exhaust note on the NA V8 engine .... the stock exhaust is SOOOOOO quiet on the non-PSE 958.1's so the catbypass pipes are a great (and cost-effective) way to really wake up your PiG. Just to close the loop on my earlier post, I ended up installing these on my 2012 Cayenne S and have before and after video clips for anyone considering the same install for a more throaty Cayenne. Sadly, online video clips don't do justice to the actual sound, but hopefully these will give you a rough idea of the improvement.
Stock Exhaust:
https://youtu.be/hJPYHjXmEhA
Fabspeed Seconday Catbypass Pipes Installed:
https://youtu.be/GGYA40NM1t0
I totally agree with the transformation of the exhaust note on the NA V8 engine .... the stock exhaust is SOOOOOO quiet on the non-PSE 958.1's so the catbypass pipes are a great (and cost-effective) way to really wake up your PiG. Just to close the loop on my earlier post, I ended up installing these on my 2012 Cayenne S and have before and after video clips for anyone considering the same install for a more throaty Cayenne. Sadly, online video clips don't do justice to the actual sound, but hopefully these will give you a rough idea of the improvement.
Stock Exhaust:
https://youtu.be/hJPYHjXmEhA
Fabspeed Seconday Catbypass Pipes Installed:
https://youtu.be/GGYA40NM1t0
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#33
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Installing my HHR (Liesteung) secondary cat bypasses this weekend on my 2009 CTTS. I'll let you know what my impressions are once I get them in place.
Cheers,
TomF
Cheers,
TomF
#34
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Live in NY
Have had Fabspeed bypass on both a 2014 cayenne turbo S and my current 2016 turbo S truck. The 2016 has PSE and with the bypass pipes the sound is very nice.
No issues, Emissions passed
Have had Fabspeed bypass on both a 2014 cayenne turbo S and my current 2016 turbo S truck. The 2016 has PSE and with the bypass pipes the sound is very nice.
No issues, Emissions passed
Last edited by RAKLAW; 03-24-2017 at 01:39 PM. Reason: typo
#35
Burning Brakes
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I'm just a messenger. I'm glad you had success, but clearly this techart dealer said multiple folks have not. He's also a dealer for tubi, akrapovik, etc. He claims to have this very conversation with folks 2-3 times a week, all certain they will pass because of what they read on the internet. He's an inspection shop for NY as well, and wasn't ambiguous at all, he's had multiple cayennes fail with the pipes installed. He's also had customers declined warranty repairs on any engine systems because of them.
I don't have a reason to doubt you, glad you passed and your dealer doesn't care. But I don't have a reason to doubt him either, so I'm thinking I'll just do a cat back exhuast and leave the cats alone. He was also clear, if you live in another state, emissions are probably not an issue. He was specifically talking NY (and implying California).
I don't have a reason to doubt you, glad you passed and your dealer doesn't care. But I don't have a reason to doubt him either, so I'm thinking I'll just do a cat back exhuast and leave the cats alone. He was also clear, if you live in another state, emissions are probably not an issue. He was specifically talking NY (and implying California).
Sometimes they just go through the motions and roll the mirror near the car without even looking at it and move on.
Other times you get the "rules are rules" Dudley Do-Right who will take forever examining every inch, including looking for signs of a gutted cat. If they find so much as a pinhole anywhere in the exhaust, you fail. No way a Cayenne would pass without secondaries.
What I find interesting is that so many are finding mechanics or muffler shops to by-pass the the cats. Around here, you'll be laughed at and told to pound sand...they're not stupid enough to risk a $25,000.00 fine.
And not having emissions testing in your area means nothing, tampering with emissions is a federal crime. Of course without testing and doing it yourself, there's next to no risk; however, most businesses would never take that risk.
#36
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Install yourself or having a shop do it?
#37
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TomF - please provide your honest feedback as soon as you have some time to spend with the CTTS with the new bypass pipes. I literally have them in my shopping cart (resonated because I hate the raspy sound), and debating on what to do. I look forward to hearing what you think.
Install yourself or having a shop do it?
Install yourself or having a shop do it?
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Cheers,
TomF
#38
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Get ready for some fun. One of the bolts is a lot of fun to access.
#39
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I'm installing them myself at my friend's shop. I have already pre-treated the bolts with penetrating oil so they are possibly easier to remove when I remove them. I hope to install them tomorrow, but it is going to depend on getting a hall pass from my better half...![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
Cheers,
TomF
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Cheers,
TomF
If you can, please share a little "Before & After" vid so we can all enjoy your sweet exhaust mod
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#40
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Cheers,
TomF
#41
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Will do. My CTTS has a Softronic ECU flash and the secondary cat delete should really help with turbo spooling. My 2009 has 550hp/557tq stock and with the tune and secondary delete it should result in about 636hp/ 637tq. I am at a modest 1.1 bar boost maximum and that is plenty!
Cheers,
TomF
Cheers,
TomF
Cheer. Can't wait to hear it.
#42
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just installed HHR secondary bypass pipes on 2009 gts a few days ago. Was a bitch getting the copper exhaust nuts off. They deteriorated so much I had to use nut extractors. Broke some studs. I found a curved wrench helpful, but like others said, getting that top nut on the passenger side is easiest from the top with extensions.
So far I like it. On cold startup there is a annoying rattle for a few seconds. Pretty throaty though.
So far I like it. On cold startup there is a annoying rattle for a few seconds. Pretty throaty though.
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#43
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This is perfect... I am in the same boat. 09 Turbo S; I was looking at the Fabspeed tune because they came out with their own. I didn't know about softronic I will check them out. I was looking to do a cold air intake, flash ECU tune, and secondary cat deletes all at once and get it over with. I love the thought of 630ish Horsepower at my foot. Not that 550 isn't enjoyable... but for under $2k we can be at 630-650... YES PLEASE!!!
Cheer. Can't wait to hear it.
Cheer. Can't wait to hear it.
Around 630hp has been my target. I am going to install Agency Power diverter valves because of their durability. That is about all. Well, except for the Rinnspeed R5s and Michellin Pilot Super Sports that will go on as soon as the snow clears up on the passes...
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Cheers,
TomF
#44
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Ok, so there's the technical law and there's reality.
Technically, yes, removing the secondary cats is an automatic fail and it's against the federal law to do so.
Reality is the truck blows more than cleanly enough with just the primary cats and also won't throw any codes with the secondary's missing.
So as long as they don't notice them missing, you'll pass fine. That's why I stayed away from polished pipes, the less bling the better.
I live ten minutes from HHR and had them install the pipes in my '06 CTTS. I was going to do I myself but I'm glad I didn't. All of the nuts between the downpipes and secondary's were rusted and rounded off, they all had to be cut off.
The truck sounds much nicer now, has a real V8 burble, like Porsche should've done. Can't really say that it's making any more horsepower, maybe it spoils a bit faster....
Technically, yes, removing the secondary cats is an automatic fail and it's against the federal law to do so.
Reality is the truck blows more than cleanly enough with just the primary cats and also won't throw any codes with the secondary's missing.
So as long as they don't notice them missing, you'll pass fine. That's why I stayed away from polished pipes, the less bling the better.
I live ten minutes from HHR and had them install the pipes in my '06 CTTS. I was going to do I myself but I'm glad I didn't. All of the nuts between the downpipes and secondary's were rusted and rounded off, they all had to be cut off.
The truck sounds much nicer now, has a real V8 burble, like Porsche should've done. Can't really say that it's making any more horsepower, maybe it spoils a bit faster....
#45
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Ok, so there's the technical law and there's reality.
Technically, yes, removing the secondary cats is an automatic fail and it's against the federal law to do so.
Reality is the truck blows more than cleanly enough with just the primary cats and also won't throw any codes with the secondary's missing.
So as long as they don't notice them missing, you'll pass fine. That's why I stayed away from polished pipes, the less bling the better.
I live ten minutes from HHR and had them install the pipes in my '06 CTTS. I was going to do I myself but I'm glad I didn't. All of the nuts between the downpipes and secondary's were rusted and rounded off, they all had to be cut off.
The truck sounds much nicer now, has a real V8 burble, like Porsche should've done. Can't really say that it's making any more horsepower, maybe it spoils a bit faster....
Technically, yes, removing the secondary cats is an automatic fail and it's against the federal law to do so.
Reality is the truck blows more than cleanly enough with just the primary cats and also won't throw any codes with the secondary's missing.
So as long as they don't notice them missing, you'll pass fine. That's why I stayed away from polished pipes, the less bling the better.
I live ten minutes from HHR and had them install the pipes in my '06 CTTS. I was going to do I myself but I'm glad I didn't. All of the nuts between the downpipes and secondary's were rusted and rounded off, they all had to be cut off.
The truck sounds much nicer now, has a real V8 burble, like Porsche should've done. Can't really say that it's making any more horsepower, maybe it spoils a bit faster....
Docwyte, does your 2006 TTS have an ecu tune?
From what Scott at Softronic told me, the secondary cat delete does allow the turbos to spool faster and generates more hp and tq. He said that it will be quite noticeable with the tune. All the other bolt-ons are expensive bling: the intake, the primary cat delete, etc... Unless you are willing to spend big bucks on headwork, upgraded turbos and willing to let longevity go, a responsible tune and the secondary cat delete is really the limit. The other modifications are going to run into five-digit territory.
Cheers,
TomF