2024-2025
2015-2023
2010-2014
2005-2009
1999-2004
1994-1998
1979-1993
Installation Time
(approx) 2 Hours
Difficulty Level:
Light to Moderate mechanical skill required.
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Find Cat-Back Exhaust for your Mustang
SLP Loudmouth II Cat-Back Exhaust (99-04 Mustang GT, Mach 1)Find parts that fit my vehicle
Item 23017
$0.00
113 Reviews
13 Answers
Our Price
$611.63
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$299.00
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Product Information
Features, Description, Reviews, Q&A, Specs & Installation
Features & Specs
- Rich, Throaty Exhaust Tone
- Loudmouth II "Bullet-Type" Race Mufflers Included
- Versatile Modular Design
- 2.5" 409 Stainless Steel Tubing
- 3.5" Polished 304 Stainless Steel Tips
- Fits 1999-2004 GT, Bullitt, & Mach 1 Mustangs
| Brand | SLP |
| Exhaust System Type | Cat-Back System |
| Exhaust System Material | Stainless Steel |
| Exhaust System Tip Finish | Chrome, Polished |
| Exhaust System Tubing Diameter | 2.50 Inch |
| Exhaust Loudness | Aggressive |
Description
More Power and Sound. This SLP system includes SLP's famous Loudmouth II "Bullet Style" race mufflers for minimal restriction, increased horsepower and an aggressive tone, that are only second to the Loudmouth "shotgun" race resonators for sound.
Modular Design. SLP's unique modular design allows you to quickly and easily switch out the mufflers or resonators to suit your driving needs. Along with the included bullet mufflers, the Loud Mouth II system is compatible with all SLP mufflers and resonators including the shotgun style Loud Mouth Resonators and the traditional-style PowerFlo Muffler.
Superior SLP Construction. This SLP Cat-Back system is made from mandrel bent 2.5" 409 stainless steel tubing for its excellent non-restrictive flow characteristics and long life. The system ends with a brightly polished 304 stainless steel 3.5" tips, that are electro-marked with the distinctive SLP logo, giving a great finishing touch and a show quality look.
Application. Designed to be a direct bolt on, this SLP Loudmouth II catback will bolt straight up to the factory Mid-Pipe without any extra modifications required on the 1999-2004 GT, 2001 Bullitt, or 2003-2004 Mach 1 Mustang to give it a rich, throaty sound.
Modular Design. SLP's unique modular design allows you to quickly and easily switch out the mufflers or resonators to suit your driving needs. Along with the included bullet mufflers, the Loud Mouth II system is compatible with all SLP mufflers and resonators including the shotgun style Loud Mouth Resonators and the traditional-style PowerFlo Muffler.
Superior SLP Construction. This SLP Cat-Back system is made from mandrel bent 2.5" 409 stainless steel tubing for its excellent non-restrictive flow characteristics and long life. The system ends with a brightly polished 304 stainless steel 3.5" tips, that are electro-marked with the distinctive SLP logo, giving a great finishing touch and a show quality look.
Application. Designed to be a direct bolt on, this SLP Loudmouth II catback will bolt straight up to the factory Mid-Pipe without any extra modifications required on the 1999-2004 GT, 2001 Bullitt, or 2003-2004 Mach 1 Mustang to give it a rich, throaty sound.
Fitment:
- 1999 Ford Mustang
- 2000 Ford Mustang
- 2001 Ford Mustang
- 2002 Ford Mustang
- 2003 Ford Mustang
- 2004 Ford Mustang
SLP M31007A
CA Residents: 
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
Installation & What's in the Box
Installation Info
What's in the Box
Hardware included:- (8) exhaust system band clamps
Tech Guides:
4.9
Customer Reviews (113)
Questions & Answers (13)
Will It Fit My Mustang
- Bullitt - 01
- GT - 99, 00, 01, 02, 03, 04
- Mach 1 - 03, 04
Fits GT, Mach 1, and Bullitt
