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Discussion Starter · #1 ·
Hey guys, I currently have CP-E's 3" catless downpipe and CP-E's 3" catback on my FoST. It's way too drone-y for me so I'm going to be keeping my catless downpipe and I'll be trading/selling my 3" catback for the stock exhaust. I'll be doing a resonator delete on the stock exhaust as well. My question is that I will need an adapter to mount the 2.5" exhaust up to the 3" downpipe, right? I bought my car with these mods so I don't have the adapters that CP-E offers with their downpipes. I sent them an email explaining the situation and asking if I could buy an adapter separately but I haven't gotten an answer yet.

Are there any "universal" adapters for this or would something like the following work?

Stock DP>Aftermarket 3 in. Catback Adapter - Subaru - GrimmSpeed
 

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I have this exact set up minus the res delete and idt I used an adapter unless I'm remembering wrong.


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Your aftermarket downpipe should match up directly with the stock exhaust. Just get a 2.5 in gasket and you should be set! GL!
 

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Discussion Starter · #5 ·
Thanks guys! I'm currently communicating with a guy who is selling his stock exhaust for ~$100 so I plan on buying that and then modifying it so I don't have to do the swap immediately.
 

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Discussion Starter · #7 ·
Thanks! Now I have another questions on a slightly different topic...the CP-E exhaust is full 3" and has two resonators near the end to reduce drone. Unfortunately, it doesn't reduce it enough to not cause me headaches on long rides. I was looking into the build I plan on doing and realized that since I DO plan on going big turbo eventually, it may be in my best interest to save the 3" exhaust....

However, what about cutting out the end of the exhaust and adding an aftermarket muffler? I plan on changing the exhaust from the center output to dual outputs at both sides and a muffler would surely make my life easier. Would adding an aftermarket Flowmaster exhaust realistically make things any quieter? Below is a pic of the CP-E exhaust and a link to the Flowmaster muffler.
FocusSTCatBack01.jpg

https://www.amazon.com/Flowmaster-9430512-Delta-Flow-Muffler/dp/B000HKVET4/ref=sr_1_68?ie=UTF8&qid=1496685793&sr=8-68&keywords=3.00+muffler
 

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You know those resonators are adjustable, right? You can loosen the clamps and slide them in and out until you eliminate the drone. That is one nice exhaust and it would be a shame to hack it up.
 
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Discussion Starter · #9 ·
You know those resonators are adjustable, right? You can loosen the clamps and slide them in and out until you eliminate the drone. That is one nice exhaust and it would be a shame to hack it up.
I'm aware and while it's definitely better most 3" exhausts, it still drones. My biggest gripe is the drone while cruising up hills, it makes me momentarily hate the car to be honest with you.
 

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I'm aware and while it's definitely better most 3" exhausts, it still drones. My biggest gripe is the drone while cruising up hills, it makes me momentarily hate the car to be honest with you.
Put this

https://www.magnaflow.com/products?partNumber=12867

Right here

FocusSTCatBack01.jpg

The muffler can be had for $75 and it should cost no more than $50 to install. It will fit there no issues. I changed my MBRP for Magnaflows.
 

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Discussion Starter · #13 ·
This is where it will be

View attachment 245538
hmm, interesting. That would most likely solve the noise issue I have with the exhaust but I would still need to make some modifications for the setup I want. I was actually considering extending the 'arms' which are used for the resonators and making them the new outputs and then shortening the original outputs and making those the new ends for the resonators. Decisions, decisions. Example below.
18986293_1489175121141157_1901763108_o.jpg
 

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hmm, interesting. That would most likely solve the noise issue I have with the exhaust but I would still need to make some modifications for the setup I want. I was actually considering extending the 'arms' which are used for the resonators and making them the new outputs and then shortening the original outputs and making those the new ends for the resonators. Decisions, decisions. Example below.
View attachment 245554
Any good muffler shop can do what you want and it shouldn't cost much.
 

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So this is what we'll need if going from a 3" downpipe to a 2.5"? I'm going to be instilling my 3" CJ Ponyparts downpipe to a Mountune catback system which is 2.5".
Yes sir - running mine and have Zero issues going from COBB DP --> Stock piping w/ magnaflow muffler installed in the same spot as the pictures above
 

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Discussion Starter · #16 ·
Hey guys, sorry for the bump. I went to a few different muffler shops last week and they're pretty much all either telling me that they won't do it or they're estimating $400-500 for everything to be done ($100 a hour). Figures that I have the hardest aftermarket exhaust to get this done....

Would it just be easier to get a custom exhaust completely made? I can buy a muffler and resonator to add to a 3" straight pipe and I have a welder at home so I'm not worried about that, I'm really just looking for the cheapest solution that will last. Will it be more cost efficient to just go to a muffler shop, have them bend the pipes and just add a Y after the rear axle and just bring two pipes straight back? Any one have any idea how much that would be? I'm sure the piping itself is fairly cheap but I'm not sure how much a shop would charge for bending and installing the Y adapter...not to mention how would they know where to bend the pipes? :disappointed:
 
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