A Modular Exhaust System to Wake Up Your 2005 GTO!
Bolt on a Loud Mouth® modular catalyst-back exhaust system from SLP on your new 2005 GTO for up to 5 extra horsepower and 5 foot-pounds of torque with the aggressive musclecar rumble your LS2 deserves. The secret to the system’s distinctive sound is a pair of stainless Loud Mouth resonators, stamped with our SLP logo. The additional performance comes from the free-flow design and our built-in PowerFlo-X™ Crossover system that borrows a power-building method used in stock car racing. The system features a pair of attractive 3.5” dual-wall stainless steel tips that look great peeking out of the GTO’s rear valence. The tips have an angle cut and can angle downward in a traditional style, or rotated 90 degrees so they match the curving shape of your rear valence. The modular design gives you flexibility to change to a quieter Loud Mouth II system in minutes by purchasing a pair of bolt-in Loud Mouth II bullet-style mufflers (#31063). The exhaust system is hand-crafted from 2.5” stainless steel, and is covered with our Limited Lifetime Warranty.
Loud Mouth catalyst-back exhaust system for 2005 GTO features:
Limited Lifetime Warranty
Aggressive musclecar rumble, louder than our Loud Mouth II system (#31561)
Modular design lets you bolt-in a pair of Loud Mouth II mufflers (#31063, not included) for a quieter system
Hand-crafted from stainless
Easy bolt-on that mounts to SLP’s header system or stock exhaust
Distinctive stainless tips that rotate for the look you want
Applications:
2005 - 2006 Pontiac GTO
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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