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Discussion Starter #1
My exhaust mods consist of Solo axle-backs and an x-pipe, and additional mods include a CAI and a Cortex tune.

I've been doing a lot of reading, and I'm hoping to determine the best exhaust mod from here. My goals are HP and sound. My current sent up sounds really mean at startup, but not so much at WOT.

1. Would you recommend Kooks mid-length headers with the built in HFC, or the standalone solo HFC? Or is there another option that I'm missing? I did lots of reading on this, and I liked the idea of the Kooks mid-length as far as header discussions go...

2. I believe either option would require me to get a custom tune and ditch the Cortex. I know guys swear by some of the well known tuners (e.g. Pat G), but would I be safe with a reputable local shop? We have a shop in Eugene, OR called FTW and they could do the header install and tune for me. The header install was quoted at $400, and the tune at $600 (it sounds like they leverage HP tuners).

Thanks!
 

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What are you local laws? Out of all the options you've listed long tube headers would give the most power and sound, and require a tune, yes.

Otherwise, Mid lengths are the next best. Then high flow cats.


In any of those cases I'd suggest a proper dyno tune anyway.
 

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I’ve had both. Solo cats , manifolds and JBA shorties, and 1.75 Kooks mids. The Mids are the best of the two. Either with high flow cats will make your exhaust too loud as it stands. The Kooks with the 3” section before the cat makes them louder at WOT. Your going to want to add some mufflers to tone it down
 

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@Slizzo no emissions laws where I’m at.

@GT Drew that’s good to know - I live in the middle of a sub development, so I definitely don’t want it TOO loud. Would replacing the x pipe with that magnaflow mid muffler so the trick, or do you mean switch out the solo axle backs for a quieter setup?
 

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The Magnaflow mid muffler in place of the x-pipe would do it . Or stock mufflers for daily and keep the Solo axle back for race days
 

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@GT Drew Would the mid muffler make it quiet at an idle though, or would headers or HFC overcome that? I actually had the magnaflow mid muffler in with the solos, and was disappointed I didn’t have much rumble... so I had it replaced with the x pipe.
 

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I've been through more exhaust than I care to admit. If I was to do it over, LT's, mids, cat, no cat, xpipe, muffled xpipe, I should have gone with oval cutouts in front of stock muffler at the start. Hold the button, wake the neighbors, hold button again, neighbors don't even know you started.
 

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I'm running the Maximizer Long tubes, Kooks hi flow cats, X pipe into the stock mufflers. The stock mufflers are the only thing holding this thing back from being 100% way too loud. Even with this set up, I just idle though my neighborhood to keep it as quiet as possible.

I'd highly recommend doing whatever set up with stock mufflers first, then decide if you need more sound.
 

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Discussion Starter #9
@JCMG8 oh that's interesting, I was looking at cutouts for a while and then decided that they weren't the best route. Perhaps I can entertain them again.

@Jeff92se That's good to know, thanks. I've watched all sorts of YouTube videos, but it's hard to get a true feel for the sound via video.
 

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Discussion Starter #11
Exactly where are you? I'm in the Seattle area
Oh nice I'm in Albany, OR just an hour or so south of Portland. With everything going on we aren't going on too many road trips, but otherwise it'd be great to link up and hear your setup.
 

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The Magnaflow 12468 muffler is long, 18” body. It does quiet the exhaust a lot. Now to compare the Solo Mach shorty and Mach are 11” and 14” respectively. The shorter the muffler the louder it is. You can buy mufflers from Solo to make your exhaust. I’ve been to their shop. My old G8 was used to test fit the 3” exhaust
 

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Discussion Starter #13
The Magnaflow 12468 muffler is long, 18” body. It does quiet the exhaust a lot. Now to compare the Solo Mach shorty and Mach are 11” and 14” respectively. The shorter the muffler the louder it is. You can buy mufflers from Solo to make your exhaust. I’ve been to their shop. My old G8 was used to test fit the 3” exhaust
Oh okay good to know - sounds like I’m in for some expensive trial and error as far as sound goes... I was starting to think I had a plan, but now I’m feeling otherwise. I’ll do some thinking/researching. Thanks!
 
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