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Old 03-06-2019, 04:13 PM   #1
SPDE RA
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Default STI type RA Exhaust.... replace/upgrade????

Been searching on here and wasn't able to find an answer help please......

Recently purchased the WRX STi type RA #285 and the specs call out "high-flow exhaust" does anyone know how much better it REALLY is? Due I start planing for installing a new exhaust system later this year?

If so, any recommendations? I like the COBB but thought I throw it out here and see what you guys think?

Thanks for the help!
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Old 03-06-2019, 05:03 PM   #2
caschnd1
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I went with the AWE Touring exhaust. No drone at all.
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Old 03-06-2019, 05:32 PM   #3
WRXnick16
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Congrats on the purchase!

I've read that RA & '19 STI have a "larger, high performance exhaust system with 50 percent less back pressure". Some people suggested that the muffler design is the same, but that it has a larger midpipe.. not sure if that's true. I haven't seen any measurements. However, Subaru stopped offering the STI performance exhaust (SPT) in 2019 so maybe the midpipe is of similar design.

Subaru states that the S209 will have "High performance mufflers with 17 percent less resistance and larger 101mm tips." I'm interested to see if any of the S209 parts will be made available to the public (conical intake, exhaust, forged pistons, hks turbo, injectors/fuel pump, etc.).

An aftermarket exhaust will likely perform a bit better than the stock system, but it'll be louder and likely weigh more unless you go with something like Cobb's titanium system. I've seen people making ~350-400whp on the stock mufflers here in California. I would only invest in a catback if you want more sound as the power gains will be negligible unless you'll be highly modifying the car down the road. A downpipe will have a much larger impact on performance. I'd prefer to go the route of an catted aftermarket downpipe with the stock catback here in California.

Last edited by WRXnick16; 03-07-2019 at 01:35 PM.
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Old 03-07-2019, 08:18 AM   #4
Burn all four
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Yea I also heard that my 2019 STI has the high-flow exhaust system. Its actually not that bad of an exhaust compared to my 2011 STI's stock one. I may just change mine out to a cat back or muffler deletes. I would love a downpipe ect but I do not want to void my warranty as I have the 8 year 80k Subaru extended warranty. The Cobb one sounds good.
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Old 03-07-2019, 08:54 AM   #5
SPDE RA
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Thanks WRXnick16 for the info, sounds like a good route to take. (down pipe + stock exhaust) as I too live in California (SoCal). Also thanks burn all four, I appreciate your input.
Happy Thursday guys!
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Old 03-07-2019, 09:00 AM   #6
TifosiWA
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I don't think just doing the DP is the way to go. My reasoning is simple, you can not change the laws of physics. If you look at the complete engine exhaust system as a whole, just opening up the air flow up stream (DP) without modification to the down stream (Cat-back), you are only creating a bottle neck situation. While there may be some gain in power, it is a castrated gain. This is why whenever anyone wishes to travel down the path of no return in the world of modding, especially with a forced induction engne, a proper cat-back system should be the first thing to be done to the car, even before software.

As for which cat-back to go with, most of them are 3" systems so other than fit and finish, it really comes down to the sound, which is subjective. I have had both AWE and Borla on two of my previous daily drivers. AWE is better fit and finish and also offers options with the exhaust tips on some of their systems, but the Borla easily wins out in the sound (Subjective) and cost. Listen to both on YouTube if you are not able to find someone local with these systems, compare them to COBB and see what you like best.
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Old 03-07-2019, 10:32 AM   #7
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The cat back adds close to nothing for back pressure compared to the cats. Think of it this way, the cat adds 100 in back pressure. The rest of the exhaust adds 8. So if you change the exhaust to a 0 (unbolt it after the cat and just don't replace it), you've still got that 100 holding you back.
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Old 03-07-2019, 12:38 PM   #8
SPDE RA
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TifosiWA: Great explanation, "bottle neck" which makes perfect sense to me since I'm in the HVAC business.... air flow is everything! Also, thank you for the suggestion of listening to AWE and the Borla system on YouTube. I'm new to the Subaru community and haven't been able to find any local meet ups around here (Huntington Beach) to go and see/listen to their rides.

Jack: Another great explanation of air flow and the restrictions our cars have. But living in SoCal I'm required to have a cat.... is there something out there I should know about?

Thanks guys!
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Old 03-07-2019, 12:54 PM   #9
Jedi03
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yup...cats are super restrictive...you are correct that it is still bottlenecked, but not to the same extent...i have consistently seen gains on all my cars with doing cat replacement/removal compared to any catback i have ever done...butt dyno to be specific
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Old 03-07-2019, 12:57 PM   #10
anarekist
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pics for comparison would be cool
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Old 03-13-2019, 04:17 PM   #11
SPDE RA
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Thumbs up going with . . . .

Quote:
Originally Posted by TifosiWA View Post
As for which cat-back to go with, most of them are 3" systems so other than fit and finish, it really comes down to the sound, which is subjective. I have had both AWE and Borla on two of my previous daily drivers. AWE is better fit and finish and also offers options with the exhaust tips on some of their systems, but the Borla easily wins out in the sound (Subjective) and cost. Listen to both on YouTube if you are not able to find someone local with these systems, compare them to COBB and see what you like best.
I've listen to the Borla with the COBB DP and that sounds sexy as hell! I plan on going with them both. Just gotta get some miles on my ride first. Thanks for the help TifosiWA!
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Old 03-13-2019, 10:50 PM   #12
TifosiWA
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Quote:
Originally Posted by SPDE RA View Post
I've listen to the Borla with the COBB DP and that sounds sexy as hell! I plan on going with them both. Just gotta get some miles on my ride first. Thanks for the help TifosiWA!

You are more than welcome, just glad that you find my recommendation useful. And more importantly, glad to see you finding a setup to your liking. Question is, will this be too loud for the new CA Exhaust Law? I think you will be okay with just Borla S-Type, but not sure if you add the COBB DP to it.
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Old 03-21-2019, 09:54 AM   #13
SPDE RA
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Thumbs up going with . . .

Quote:
Originally Posted by TifosiWA View Post
You are more than welcome, just glad that you find my recommendation useful. And more importantly, glad to see you finding a setup to your liking. Question is, will this be too loud for the new CA Exhaust Law? I think you will be okay with just Borla S-Type, but not sure if you add the COBB DP to it.
Update: I ordered my new exhaust yesterday. After emailing back and forth with COBB with regards to sound dba levels and HP gains I ended up going with the "COBB Titanium Cat Back".Weighs in at 24 lbs. (half of s.s.) 90 dba max on high end, sounds good (IMO) quality build and backed by a great company... COBB.

Additionally, COBB DOES NOT have a map to work with a DP and exhaust. They explained, that testing on the dyno they found the "stock" fuel pump could not keep up. They recommended, when installing DP with the exhaust, you should consider upgrading the fuel system. Then their Stage 2+ map would work perfectly.

If anyone is interested, I would be happy to email you the emails from COBB to better understand what I hope I was able to explain above.
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Old 03-21-2019, 10:14 AM   #14
TifosiWA
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Quote:
Originally Posted by SPDE RA View Post
Update: I ordered my new exhaust yesterday. After emailing back and forth with COBB with regards to sound dba levels and HP gains I ended up going with the "COBB Titanium Cat Back".Weighs in at 24 lbs. (half of s.s.) 90 dba max on high end, sounds good (IMO) quality build and backed by a great company... COBB.

Additionally, COBB DOES NOT have a map to work with a DP and exhaust. They explained, that testing on the dyno they found the "stock" fuel pump could not keep up. They recommended, when installing DP with the exhaust, you should consider upgrading the fuel system. Then their Stage 2+ map would work perfectly.

If anyone is interested, I would be happy to email you the emails from COBB to better understand what I hope I was able to explain above.
Excellent choice with COBB catback too, a notch above Borla in quality and price, especially with the Titanium, add weight saving too. So you are going Stage 2 now?
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Old 03-21-2019, 02:35 PM   #15
SPDE RA
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Quote:
Originally Posted by TifosiWA View Post
Excellent choice with COBB catback too, a notch above Borla in quality and price, especially with the Titanium, add weight saving too. So you are going Stage 2 now?
Thanks..... not yet. Need to install everything I just purchased..... It's all still in boxes in the garage!
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