1999-2004 Mustang GT 4.6L SLP "Loud Mouth" Exhaust System (Modular)

SLPs Mustang LoudMouth has always been the best performing cat-back exhaust in the business. Now its the most versatile, too! Using groundbreaking modular technology first seen on our Mustang X-pipes, we've developed a system that can be quickly reconfigured to fit changing performance, noise level, and sound quality requirements. Simply loosen a few band clamps, swap muffler types, re-tighten, and you're done. No other system offers this level of performance and adaptability!

• Along with the included resonators, the Mustang LoudMouth system is compatible with two all new SLP mufflers, the bullet-type LoudMouth II race unit (#31064) and the traditional-style PowerFlo (#31065). Buy all three for complete control over your Mustangs sound and performance characteristics.

• NOTES: Includes LoudMouth resonators. LoudMouth II and PowerFlo mufflers sold separately.

FEATURES:

• Includes our infamous LoudMouth resonators for virtually zero flow restriction and the meanest sound around
• Employs SLPs exclusive modular technology, making it possible to switch between muffler and resonator types in a matter of minutes
• Dyno-proven to outperform competitive resonator-type exhausts
• Engineered and built to OEM standards to ensure proper fit
• Constructed entirely from mandrel-bent 304 stainless steel
• Features show quality polished resonators and 3.5" double-*wall tips with electromarked SLP logo
• For 1999-2004 GT and Mach I models

• SLP Part Number: M31007

• 1999-04 SLP LoudMouth 1 :

Offers the most aggressive exhaust note available today for your Mach 1, Cobra, and GT Mustang. With no internal packing/baffling of any kind the LM1 series allows the absolute biggest HP gains to be seen along with the loudest exhaust output in the industry. Due to the "straight shot" non baffled design of these mufflers we recommend only using the LM1 catback with the stock headers and catted mid-pipe. You will have a good amount of resonance in the vehicle with this system while driving under a load & also at freeway speeds.

• 1999-04 SLP LoudMouth II :

From the exterior looks the same as the LM1 system but offers a completely new design internally. The LoudMouth II system offers a fiberglass packed wall between a perforated 2.5" tube and the resonator's outer case. This design helps to reduce the in cabin resonance and also to lower the exhausts volume. The LM2 system is still considered aggressive when compared an oval cased muffler such the SLP Power-flow. We recommend using the LM2 catback with stock headers and catted mid-pipe. Although some customers will run after market headers and high flow catted mid-pipes to obtain more power and consequently increase the exhaust's total volume.