Give your 2008-09 Pontiac G8 GT 6.0L race-proven performance and a powerful deep muscle-car sound to match, with a Loud Mouth™ rear-section exhaust system from SLP Performance Parts. This affordable, easy-to-install kit eliminates the two rear factory mufflers entirely, drastically reducing backpressure for enhanced power and a mind-blowing performance sound. (note: This Kit DOES create interior cabin resonance) This system will give your G8 GT a 10hp increase over stock. This exhaust kit eliminates the two rear mufflers and replaces them with two 16 long 2.5 O.D. stainless steel tubes. Combined with our all-new custom tailored G8 GT 304SS tip, you'll really feel, hear and best of all SEE the difference!
G8 GT 6.0L Loudmouth™ Axle-Back Exhaust System features:
Maximum Flow with straight 2.5 Tubing
Lighter than the OEM assembly
Installs in under 30 minutes
Constructed entirely from stainless steel
Two custom tailored G8 GT 304SS tips
Emissions legal in all 50 states
Includes pre-welded hangers detailed instructions, and all necessary installation hardware
Covered by SLP's Performance Guarantee and limited lifetime warranty
Applications:
2008 - 2009 Pontiac G8
SLP Exhaust Type Descriptions/Definitions/Details: (use as a guide to the exhaust system on this page for details about the muffler type.)
Model
Type
Sound Characteristics*
Noise Level*
Bullet-Type Open Resonator (or muffler delete)
Extremely aggressive; powerful high- and mid-range tones with
moderate resonance
Muffling, Bullet- Type Resonator
Similar to original Loud Mouth, but with a throatier tone and reduced
resonance
Straight-Through "Traditional" Muffler
Deep, rich, and mellow; minimal resonance
*
Volume and sound quality will vary based on engine and exhaust-system
specifications. Loudmouth also refers to some systems without any resonators such as the 2010 Camaro Loud Mouth and the 2005 Mustang Loud Mouth Axle backs where the mufflers are removed altogether. Images below are representations in order to better understand the differences.
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