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      04-15-2026, 07:29 AM   #1
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Sound/Tone Exhaust/DP Question

For deeper, better "tone":
  1. What is the best sounding valved axleback?
  2. Should I go catted DP first? Or axleback first?
I know "1" is very subjective. Searching the forums yields "Remus", seems it is on indefinite backorder everywhere I looked. The others I am considering are AWE and AFE.
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      04-20-2026, 06:30 PM   #2
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Taking a life lesson from Mike at xTreme Powerhouse, do to the DP first (catted, catless just makes your car sound like a 1940 John Deere 4010 and rattles like a mofo - my thoughts, not Mike's lol). Then do the axle back if you want more tone.

I started with a VSRF catted DP which started with fitment issues and sounded HORRIBLE. Then went to the ER DP which mounted properly and tone was spot on.

I did also do the Active Autowerke cat-back. The combo sounds great but I did weld the OEM left exhaust valve into the AA cat-back left tip. Stopped the "boomy" tone when idling.

But to answer your initial question, the DP will tend to give more "depth" to the sound, the catback the actual sound. I have a BM3 tune, so I wanted to go to stage 2 (hence the DP). Hope that was helpful?
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      04-20-2026, 08:06 PM   #3
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Yeah I'd def go DP first. It's performance + sound. You can always adjust after that - axleback, or remove one of the resonators.

It's all personal preference, but I went with a catted DP (Active Autowerke w/ Gesi cat). Reasons are (1) passing NYS inspection, (2) didn't want the smell of catless, and (3) less rasp in the exhaust note. Downsides of catted are (1) price and (2) you could still run into some restrictions with higher horsepower builds depending on the turbo.
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      04-21-2026, 06:54 AM   #4
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Quote:
Originally Posted by Wires View Post
Taking a life lesson from Mike at xTreme Powerhouse, do to the DP first (catted, catless just makes your car sound like a 1940 John Deere 4010 and rattles like a mofo - my thoughts, not Mike's lol). Then do the axle back if you want more tone.

I started with a VSRF catted DP which started with fitment issues and sounded HORRIBLE. Then went to the ER DP which mounted properly and tone was spot on.

I did also do the Active Autowerke cat-back. The combo sounds great but I did weld the OEM left exhaust valve into the AA cat-back left tip. Stopped the "boomy" tone when idling.

But to answer your initial question, the DP will tend to give more "depth" to the sound, the catback the actual sound. I have a BM3 tune, so I wanted to go to stage 2 (hence the DP). Hope that was helpful?
YES! VERY! Thank you!
I was looking at the ER catted DP. Did it throw a CEL?
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      04-21-2026, 06:57 AM   #5
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Quote:
Originally Posted by 2Wolves View Post
Yeah I'd def go DP first. It's performance + sound. You can always adjust after that - axleback, or remove one of the resonators.

It's all personal preference, but I went with a catted DP (Active Autowerke w/ Gesi cat). Reasons are (1) passing NYS inspection, (2) didn't want the smell of catless, and (3) less rasp in the exhaust note. Downsides of catted are (1) price and (2) you could still run into some restrictions with higher horsepower builds depending on the turbo.
Thank you! I'm not planning to go much higher on HP. I love this car and want it to last, so performance upgrades will be mild, maybe a 10-20% hp increase at most down the road.
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      04-21-2026, 07:05 AM   #6
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Quote:
Originally Posted by 0_gravity_0 View Post
YES! VERY! Thank you!
I was looking at the ER catted DP. Did it throw a CEL?
No CEL. The VSRF one would once a day, but the ER one has been on for ~40k miles now, no CEL just worked.

What I found was the VSRF DP's that had 5" cat's have to increase from a smaller pipe to 5" and then back down again. That just made a megaphone effect which sound horrible with a lot of drone at idle, cold start, cruising up a road under load, etc.
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      04-21-2026, 07:10 AM   #7
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Has anyone heard the AFE axleback in person? There's only a handful of youtube videos and it's hard to judge from those. @mike@x-ph.com
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      04-21-2026, 07:11 AM   #8
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Quote:
Originally Posted by Wires View Post
No CEL. The VSRF one would once a day, but the ER one has been on for ~40k miles now, no CEL just worked.

What I found was the VSRF DP's that had 5" cat's have to increase from a smaller pipe to 5" and then back down again. That just made a megaphone effect which sound horrible with a lot of drone at idle, cold start, cruising up a road under load, etc.
Roger that! Thanks again!
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      04-23-2026, 12:01 PM   #9
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Can anyone confirm that my DP is stock or not?
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      04-23-2026, 01:09 PM   #10
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Quote:
Originally Posted by 0_gravity_0 View Post
Can anyone confirm that my DP is stock or not?
imo, it is not stock. if you search images of OEM and aftermarket downpipes you'll see notable differences.
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      04-23-2026, 01:55 PM   #11
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Quote:
Originally Posted by alohasurftoad View Post
imo, it is not stock. if you search images of OEM and aftermarket downpipes you'll see notable differences.
well, balls.....

I gotta figure out what all has been done to this car
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      04-23-2026, 01:58 PM   #12
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      04-23-2026, 02:00 PM   #13
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If it is indeed aftermarket, I wonder if it's catless
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      Yesterday, 06:21 PM   #14
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If your car smells like a 1965 Chevelle or a lawn mower, it's catless. It is VERY obvious. High flow cats will have a slight fuel smell IMO.
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      Today, 08:08 AM   #15
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Quote:
Originally Posted by Wires View Post
If your car smells like a 1965 Chevelle or a lawn mower, it's catless. It is VERY obvious. High flow cats will have a slight fuel smell IMO.
Mine does many times
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