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hello. i have a full stock 09 G8 GT. i am thinking about getting an exhaust system done and maybe a cold air intake. could you get some advice on these 3 options or maybe another option. thanks

1.G8 GT and GXP Mach Shorty Cat-Back (most aggressive kit)

2.G8 GT and GXP Mach Cat-Back (most popular mid-range aggressive kit)

3.G8 GT and GXP Axle-Back

price doesnt matter. thanks in advance.
 

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If you do a search on YouTube, you can listen to just about every combination you can think of. The solo axle backs have caught my ear and I think that's what I'm going to go with.
 

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I would listen to you tube videos first. Even the videos don't always tell the whole story. I like them LOUD!!!!!! I just put long tube headers on/no cats and no rear mufflers and figuring it would be crazy loud I took my x pipe off and put a jones mid muffler on and the car is still too damn quiet for my taste. To each his own though. If you like it loud I would look into headers, with/without cats maybe an x pipe and some solo's or SLP axle backs. I have heard Magnaflows and others can cause drone issues. Good luck sir.
 

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Yea. Videos only do so much justice. They may sound a little different in person.

Solo is very popular. If you go with a cat back and c.a.i. , you'll be borderline for a tune. Get headers and hfcs and you'll definitely need a tune. Also ,how loud do you want to get o.p?

Hey supersnake. Do you have a sound clip of yours? Interested to hear or at least get an idea as to how loud you are with your current set up
 

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Most important question, will you be keeping AFM? The louder the exhaust, the more annoying the changeover. Jpipes (Solo) fix drone, but not the AFM changeover. Corsa does a pretty good job with both.
 

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GXPaycheck makes an excellent point I fully agree with. The Youtube videos aren't going to give you a feel for what the AFM changeover will sound like. IMO, the GXP exhaust is about as loud as a normal person will be happy with if AFM is still in place. Disable AFM and you'll be able to go as loud as you want without the annoying AFM changeover sound.
 

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I have the Solo axle back and AFM turned off, big improvement over stock. You could start with this and work your way forward if you want more; if you completely replace the stock system first and find you don't like it, you're kinda stuck. Opinions on this approach may vary. Another option is to try and find a G8 group in your area (if there is one) and listen to different exhaust setups in person.
 

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No unfortunately I don't. I kind of suck at uploading pictures and videos . When you first fire it up its pretty loud and then it gets really tame maybe not much louder than stock while driving and when you put your foot in it it'll open up but it's just not what I'm use to.
 

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OP you can have fricken long loud headers, expand the noise using a 3 1/2" megaphone, 4" race cats, then straight through all the way back to X-pipe at rear (basically as loud and deep as possible), and still be free of unwanted harmonics. For bugger all.
I run custom tuned exhaust as above (see link in sig.) plus have AFM tuned to be active more often - zero drone.
The answer I found after much experimentation (Google pir4te AFM) is put X-pipe at tuned location of the second harmonic, and install HSV bimodal rear cans for $300. That is all.
 

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I vote for option 1. I'm running Solo's mach shorty catback along with mid length headers and I personally don't think it's loud enough. It's got a nice tone, but doesn't get LOUD unless you're getting on the throttle.
 

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Discussion Starter #12
thanks for the responses. I am not wanting it super loud just want it louder than stock and feel like this sounds awesome for a V8. i am also on the edge of just keeping it stock because its my daily car and the louder exhaust may get annoying after months.
 

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thanks for the responses. I am not wanting it super loud just want it louder than stock and feel like this sounds awesome for a V8. i am also on the edge of just keeping it stock because its my daily car and the louder exhaust may get annoying after months.
That's what I thought to begin with also. I don't want it too loud I told myself. On my GT I started with just the axlebacks because they were alot cheaper than the catback. After a few months I wanted it louder. I proceeded to replace the mid muffler with an x-pipe. This held me over for a while and was relatively inexpensive. It had a great sound, but just wasn't loud enough. I wrecked my GT and got a GXP a few months later. This time I knew I wanted the catback and I got the loudest one that Solo offered. Even after Steve from Solo tried to talk me out of the Mach Shorty. He said it might be too loud also. I'm glad I got the Mach shorty it sounds great and even the wife approved. This lasted for about a year then I wanted more sound, so I bought mid length headers. With headers, the exhaust sounds AWESOME! Only thing now is I wish I would've got the long tubes for just that extra bit of volume. Oh well. My point is that it never ends. You'll get used to the volume of the exhaust after a while and think it's "too quiet" and you'll regret not getting the "louder" exhaust.

I'll also add that the Solo's are so good at cancelling drone that it's really quiet inside the car when you're just cruising. You get the best of both worlds - quiet inside & great sound for outside the car.
 

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Discussion Starter #14
the wife approved the mach shorty, i may end up getting that one. Steve told me axel back for noise but cheap and no HP. mach shorty is louder than the mach. ive heard many youtube videos and just wish i could hear the 3 in person lol.
 

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I picked up the Borla cat back from Maryland Speed love it. Then added SLP long tubes with the hi flow cats. Perfect daily manners and shows balls when needed.
 

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I have Solo high flow cats and a Borla cat back and am very pleased with it. I get lots of compliments on the sound, especially when I start it. There is a slight drone in the 1800 rpm range but it's not hard to keep it out of that area. :D
 

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If any of you guys are in the Southeast you may want to come to the 6th Annual Southeast G8 Extravaganza at the end of April. There will be around 100 G8s and at least 50 different exhaust combinations for your listening pleasure.

http://www.g8board.com/forums/showthread.php?t=230969
 

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the wife approved the mach shorty, i may end up getting that one. Steve told me axel back for noise but cheap and no HP. mach shorty is louder than the mach. ive heard many youtube videos and just wish i could hear the 3 in person lol.
Have you considered the SLP Powerflo axleback. Really nice sound but not loud with stock exhaust. Steer away if you are going to go with headers in the future as when I put on the kooks headers and Xpipe they droned and I went back to the stock mufflers to eliminate, but it didn't do that with the stock exhaust.
 

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he edge of just keeping it stock because its my daily car and the louder exhaust may get annoying after months.
This was one of the reasons i went with cut outs. I can be loud or quiet. Not as quiet with the headers on but still pretty quite. It used to sound stock without the headers. Mine is quite loud and so i don't know if you want to go that route though. Not insane loud but loud : )
 
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