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      02-24-2021, 09:12 PM   #1
Benh13
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catted DP advice

Hi all,
Looking to do an exhaust mod for a reasonable price. Thinking about doing just a catted DP as the CTS one is sub $400. Do you think it would make enough of a sound difference if thats my only exhaust mod? Also, does anyone know if it would pass emissions in NY/CT? Curious to hear everyone's responses. Here is the link to what I'm thinking of buying...
Appreciate the help.

https://www.urotuning.com/products/c...0aAnRhEALw_wcB
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      02-24-2021, 10:03 PM   #2
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OEM to catted DP with a stock exhaust is an almost imperceptible change in sound. I did that with fabspeed. Cold start will be very slightly louder, but only if you listen carefully. In the car driving around you probably wont notice a difference at all. If you add a resonator delete on top, the car sounds good IMO, but its still very mild.







Note, when interpreting exhaust videos, the car sounds louder (and better) from behind than inside the car.

CTS turbo DP will throw a CEL and not get your catalyst monitor into the ready state. Whether or not you pass depends on if your state allows you to have 1 monitor not ready, and if that is your only one not ready.
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      02-24-2021, 10:58 PM   #3
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Quote:
Originally Posted by Benh13 View Post
Hi all,
Looking to do an exhaust mod for a reasonable price. Thinking about doing just a catted DP as the CTS one is sub $400. Do you think it would make enough of a sound difference if thats my only exhaust mod? Also, does anyone know if it would pass emissions in NY/CT? Curious to hear everyone's responses. Here is the link to what I'm thinking of buying...
Appreciate the help.

https://www.urotuning.com/products/c...0aAnRhEALw_wcB
Guys in NY complain all of the time about having to reinstall their stock downpipes to pass emissions. So your best bets to pass emissions with an aftermarket catted downpipe are the only two that I know of that promise no Check Engine Light.

The Fabspeed Sport Cat, which I have, is considered the best because of its HJS catalytic converter. But it's price just increased tremendously. The next best is the Active Autowerke catted downpipe. I believe that is about $950.

Quality wise the next best catted DPs, which don't guarantee no CEL, are the Wagner and the Evolution Racewerks. You could get one of those but keep your stock DP handy in case you need it to pass emissions.

Photo is of the Fabspeed after ceramic coating.

Hope this helps!
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      02-25-2021, 12:16 AM   #4
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I would not get the Wagner DP. Doesn't pass emissions, still throws a CEL, and way too many fitment issues reported recently.
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      02-25-2021, 02:30 PM   #5
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Bargain exhaust mods

Appreciate the help everyone.

Aside from catless DP and resonator delete what would be the least expensive way to get the most sound? Muffler delete?

Looking for no drone.
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      02-25-2021, 02:52 PM   #6
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Quote:
Originally Posted by Benh13 View Post
Appreciate the help everyone.

Aside from catless DP and resonator delete what would be the least expensive way to get the most sound? Muffler delete?

Looking for no drone.
You will almost certainly drone with a muffler delete. Its possible it wont be TOO bad if you keep OEM DP and stock resonator, but the muffler is the most important part of the system for reducing drone.

Catless DP with stock exhaust (including resonator) will give you both performance and sound.

Resonator delete for ~$100 with OEM DP and stock axleback will only be a modest increase in sound.

I'm sure you can find videos of all this stuff online. The challenge you will face is that the cheapest ways to increase volume also introduce the most drone, since the "proper" way to get a better sounding/louder exhaust without drone is to get a completely different system with a different design.
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      02-25-2021, 03:25 PM   #7
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CG Precision DS-01 Catted Downpipe has never produced a check engine light on my F30, so there are more than 2 options out there. CG also has a larger diameter for more airflow than Fabspeed (and is quite a bit cheaper). Sold by Mike @ x-ph.com

I haven't tried to pass CA emissions with it yet, though.
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      02-25-2021, 03:28 PM   #8
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Quote:
Originally Posted by mlev View Post
CG Precision DS-01 Catted Downpipe has never produced a check engine light on my F30, so there are more than 2 options out there. CG also has a larger diameter for more airflow than Fabspeed (and is quite a bit cheaper). Sold by Mike @ x-ph.com

I haven't tried to pass CA emissions with it yet, though.
Yes this is another no CEL option, but AFAIK its still built to order, so lead time can be several weeks or longer.

Also, in order to take advantage of their 3.5'' outlet option, you need a 3.5'' exhaust, which very few people have. Otherwise, its the same diameter as all the other DPs.
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      02-26-2021, 12:41 AM   #9
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Quote:
Originally Posted by thejeremyman9 View Post
Yes this is another no CEL option, but AFAIK its still built to order, so lead time can be several weeks or longer.

Also, in order to take advantage of their 3.5'' outlet option, you need a 3.5'' exhaust, which very few people have. Otherwise, its the same diameter as all the other DPs.
I've got the CG 5" Race Catted Downpipe, which has a 4" Turbo Flange and connects to stock outlet flange (paired with AWE catback). So still more airflow regardless.
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      02-26-2021, 10:10 AM   #10
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Quote:
Originally Posted by mlev View Post
I've got the CG 5" Race Catted Downpipe, which has a 4" Turbo Flange and connects to stock outlet flange (paired with AWE catback). So still more airflow regardless.
The fabspeed cat section at 5'' (at least) also. I get the CG is a good DP, but i don't see any evidence it flows more than fabspeed or some of the other equivalently sized options with comparable cat density/cell lol.
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      02-26-2021, 10:38 AM   #11
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I took off my VRSF catted downpipe due to too much sound. May put it back on to see if it was all in my head.
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      02-26-2021, 10:46 AM   #12
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Quote:
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I took off my VRSF catted downpipe due to too much sound. May put it back on to see if it was all in my head.
What exhaust? I've noted before that the impact of a catted DP on sound increases when you already have a louder exhaust than stock. With stock exhaust the change is very small, but with a exhaust that is already louder than stock, going from OEM DP to catted DP will have a larger impact.
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