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Discussion Starter #1
Finally got my car up on a lift tonight to install my new exhaust setup. We deleted the mid-muffler and resonators and installed an X-pipe to two GXP axlebacks. The sound is definitely not terrible. It's a little high-pitched, but that's what you get when you have a V6, no low V8 rumble. It sounds fantastic on idle, revs good under full-throttle, absolutely ZERO drone and 1500-2500RPMs (55-75MPH or so).

I'll try and get a fly-by video up soon. I personally think it sounds a lot better driving than it does revving it to 4k RPMs while parked.

Stock (heavy-ass) exhaust:


New Stuff:




Clean welds:



Bolted Up:



GT Tips Before:



GXP Tips After:



Rev in Park Before:

Rev in Park After:

Startup and Rev:

 

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Looks and sounds good! Need some exterior vids so we can hear it under load. If you're ever willing to give up those axle-backs let me know...

But seriously, job well done.
 

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Discussion Starter #3
Thanks! Considering what I paid for those axlebacks I don't think I'll be getting rid of them in the near future. I've got a full set each of V6 and GT stockers though! ;)
 

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sounds great...
 

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Sounds great, good work!
 

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Just curious....most times you see guys putting the X-pipe up towards the front. Any reason or benefit to putting it all the way back like yours?
 

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Discussion Starter #9
I don't really think it matters all that much. You'll hear guys talking about rubbing oil or drawing crayon on the pipes to see where it stop burning, or to look for the blued spot on the steel or whatever, but at the end of the day it's a little ~270HP V6 and it won't make much of a difference in terms of performance no matter where it's placed. I put it towards the rear of the car because I didn't have a choice, that's where it was on Corey's G8. :)
 

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Actually the placement of the cross pipe can make a difference in power and torque or where it peaks at.

I don't remember which is which, but you place it closer to the exhaust manifold/headers to either increase HP or TQ and you move it farther away to do the other. I just can't remember which is which.

I do remember when I had the magna flow prototype exhaust, they put the X pipe up front near the tranny.
 

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Not to get off topic but Karma i like your new signature,looks profesional..
 

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Very nice job Karma! My x-pipe is in the same place.

-Dennis-
 

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Thanks for taking the time to do this! That combo sounds nice, especially in the upper rpms. Any burble on decel?

I'll have to keep my.eyes open for a set.

-Dennis-
 

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Sounds good.

Guess I don't understand the ESC on/off part? How would that matter?
 

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Sounds good karma.Nice option to go with GXP mufflers.
 

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Yeah, definitely sounds better than stock as we've all found out on the 6s and GTs! I think it has a nice, refined sound to it. Not too obnoxious, but lets others know you're driving a sports sedan. Nice work!
 

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Discussion Starter #20
Thanks everyone. I went with standard 2.25" piping.

@TLS: With ESC turned on, if the car senses even slight wheel slippage (not necessarily even full wheel spin) it will retard the ignition. I didn't think the tires would break loose anyway (low HP car + super-grippy Potenzas = not going to happen) but I didn't want to take the chance of having an embarrassing hard launch followed by a sharp drop in RPMs and thus a change in the exhaust note.
 
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