Bolt on a Loud Mouth or Loud Mouth II 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 distinctive sound is a pair of stainless Loud Mouth resonators, stamped with the SLP logo. The additional performance comes from the free-flow design and SLP's 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 (available separately). If you already have
the Loud Mouth II and decide you want something more aggressive, the Loud Mouth mufflers can be purchased separately as well (email us for special ordering). The exhaust system is hand-crafted from 2.5 inch 304 stainless steel, and is covered with SLP's Limited Lifetime Warranty.
- Limited Lifetime Warranty
- Aggressive musclecar rumble (Loud Mouth System louder than Loud Mouth II system)
- Modular design lets you bolt-in a pair of Loud Mouth or Loud Mouth II mufflers if you decide to change the sound.
- Hand-crafted from 304 stainless
- Easy bolt-on that mounts to SLP header system or stock exhaust
- Distinctive stainless tips that rotate for the look you want