How to install a SLP Loudmouth Catback Exhaust on your 1999-2004 Cobra Mustang

This Mustang Parts Installation Guide Works For

SLP Loudmouth Catback Exhaust (99-04 Cobra)DOWNLOAD PDF

Tools Required

Installation Time: (approx) 2 Hours

Installation

Item #QuantityPart NumberDescription
1.1310304786 Front Driver-side Intermediate Pipe
2.1310304787Front Pass-side Intermediate Pipe
3.1310304788Rear Driver-side Intermediate Pipe
4.1310304789Rear Pass-side Intermediate Pipe
5.2310013919 Resonator
OR
5.2310013818Bullet Muffler
6.1310304781Driver-side Tailpipe
7.1310304780Passenger-side Tailpipe
8.2310305785ATailpipe Tip
9.83081443802.5 in. Exhaust Clamps
10.23073347882 1/2” Ball Flange
11.1*********Instructions

Warning: SLP recommends allowing the vehicle to cool (not running) for five hours before beginning the installation. SLP recommends wearing safety glasses for the complete installation.

INSTALLATION INSTRUCTIONS

  1. Raise the vehicle to allow for a sufficient work area underneath the vehicle. A vehicle lift will make this installation much easier, however, raising the vehicle can be accomplished using ramps or a jack with jack stands.
  2. Remove the old exhaust from the vehicle by unbolting the 2 flanges from the H-pipe and removing the exhaust hangers from the rubber insulators. Leave the rubber insulators attached to the vehicle.
  3. Both the driver & passenger side intermediate pipe assemblies consist of a resonator, a front intermediate pipe, and a rear intermediate pipe. Begin by placing the front of the driver side intermediate pipe (the shorter of the two front pipes) onto the ball flange on the h-pipe and slide the flange onto the studs. Thread the nuts onto the studs but leave them loose enough to allow later adjustment.
  4. Place an exhaust clamp onto the inlet of one of the resonators or mufflers. The inlet side is easily identifiable because it is larger and slotted. Slide the inlet of the resonator or muffler over the end of the driver side intermediate pipe and loosely tighten the clamp.
  5. Insert the hanger on the driver side rear intermediate pipe into the rubber insulator. Then place an exhaust clamp onto the front of the rear intermediate pipe and slide the pipe over the outlet of the resonator. Tighten the clamp but leave it loose enough to allow later adjustment.
  6. Slide one of the supplied 2.5" exhaust clamps onto the front of the driver side tailpipe, slip the tailpipe onto the intermediate pipe, and slide the hanger into the rubber insulator. Loosely tighten the clamp.
  7. Place an exhaust clamp onto the end of one of the tailpipe tips, slide the tip onto the driver side tailpipe, and slide the hanger into the factory tailpipe hanger. Loosely tighten the clamp.
  8. Repeat this entire procedure (steps 3 through 7) for the passenger side.
  9. Now adjust all the pipes until the tips are located as desired and all the pipes have enough clearance from all suspension, brake lines, fuel tank, driveline, and body parts.
  10. .

  11. Tighten all the clamps and fasteners working from the H-pipe back, while checking and maintaining correct tip location along the way. The h-pipe flange studs/nuts should be tightened to 26 lb/ft.
  12. Start the vehicle and inspect for leaks.
  13. Double-check all fasteners and clearances after test driving. Adjust as necessary.

Dear SLP Enthusiast,

SLP LoudMouth Exhaust Systems DO include a muffler. While it does not “look” like the traditional muffler, it is indeed a muffler by definition.

The muffler (aka resonator - actually a misnomer or ill-understood word) was designed by SLP to smooth the exhaust gas pulsations by methods of wave rarefaction to make them as inaudible / quiet as possible. This is a type of reflection muffler; Most people are much more familiar with more common 'absorption type mufflers', which typically include internal perforations, sections, and/or absorption insulation.

More simply put, a muffler exists and was designed with intent to reduce exhaust noise.

The Specialty Equipment Manufacturers Association (SEMA – www.sema.org) has staff dedicated to representing the aftermarket industry in regulation/legislation pertaining to aftermarket parts. SEMA is an excellent source for further information and/or news and updates regarding the latest laws governing aftermarket parts.

The SLP Loud Mouth exhaust system is 50 state, emissions legal. It will not adversely effect emissions. Every local jurisdiction creates and enforces their own laws regarding ‘noise’. Local jurisdictions have the ability to write more detailed and stringent laws regarding noise - but commonly do not outlaw 'replacement exhaust systems'; Unless they have their own specific design criteria for a 'muffler', which specifically excludes reflection type mufflers, the Loud Mouth would typically be acceptable. Only actual laboratory decibel measurements are a fair measurement of a muffler’s effectiveness to quiet exhaust and should be required and completed to judge an exhaust system. Most jurisdictions do not have the ability to measure noise levels accurately. The testing is very subjective if not properly and accurately completed.

Due to the nearly infinite number of local juridictions, 'related noise regulations/laws', and their high frequency of change, SLP does not participate and/or represent customers, companies, shops, technicians, or sellers in any litigation, traffic or legal matter regarding or related to the legality of an SLP exhaust system and disclaims any responsibility. It is solely the responsibility of the customer to investigate and verify whether or not SLP products are legal for use. SLP recommends checking local legislature for specific laws regarding the legality of aftermarket exhaust systems.

SLP Performance Parts