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ONLY WORKS ON SLP EXHAUSTS: 31042,31042A,31043,31043A
Get maximum flexibility from your modular SLP cat-back system with our new Loud Mouth II bullet race muffler. It offers flow and performance similar to that of our original Loud Mouth™ resonator but features a ceramic-wrapped, perforated core that reduces high-frequency noise and in-car resonance. Each Loud Mouth II muffler is constructed from hand-polished 304 stainless steel and embossed with the classic SLP logo.
Fits Camaro and Firebird Models.
|Model||Type||Sound Characteristics*||Noise Level*|
(or muffler delete)
|Extremely aggressive; powerful high- and
mid-range tones with moderate resonance
|Similar to original Loud Mouth, but with
a throatier tone and reduced resonance
|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.
History and information about SLP Performance and their products.
Since 2001, LMPerformance has worked closely with SLP Performance to offer customers a wide range of performance enhancements to the American muscle car, perhaps the best known of which is its SLP loudmouth mufflers exhaust systems. With our SLP Performance parts line we have helped customers transform late-model rides into modern musclecars like the Camaro SS and Pontiac Firehawk. What initially impressed LMPerformance was SLP being the first company in the performance aftermarket to develop and manufacture a 50-state emission-legal performance package -- specifically for V8 Camaros and Firebirds. LMPerformance carries SLP's best-in-class performance upgrades in the following product categories: TVS Supercharger Packages, Blackwing Cold Air Intakes, SLP Exhaust Tips, Powerflo Headers, SLP Accessories, SLP Suspension, SLP Brake Kits,SLP Wheels.
The range of applications offered by us with the SLP line is equally as wide. Below is just a partial list: Chevy Camaro,Corvette, GM/GMC Trucks and SUVs, Pontiac Firebird, GTP, G8, GXP and GTO, Ford Mustang and F-150, Dodge Challenger, Charger, Magnum and 300.
Established in 1987, SLP has stood for quality performance enhancements for late-model American Muscle cars from the beginning and it continues to work with vehicle manufacturers. LMPerformance with the above mentioned product lines and parts carries SLP’s entire selection of dyno-tested engine components, exhaust systems, and bolt-on power adders, plus the dress up accessories and incredible wheels your car or truck needs. We are impressed in how only SLP combines this level of OEM quality and aftermarket performance.
We quote SLP's initial claim to fame which says it all: True to its name ("Street Legal Performance"), and their vision of SLP's part program is "to not just provide performance, but to do so with the best engineering practices and quality possible, far exceeding the industry standards".
You would be hard pressed to question the quality of a product from a company that has been in business as long as SLP and at the same time has garnered an inestimable reputation across the spectrum of vehicle owners from everyday drivers to high performance aficionados. The multiplicity of products offered by SLP is a testament to their desire and willingness to go the extra mile to see to it that you get the right part for your car to improve its functioning whether it be driving to work or aiming for the finish line. ROUSH, the epitome of late-model Ford performance tuning, acquired SLP, the epitome of the late-model GM performance tuning and responsible for the supercharging of Regal GSX, Grand Prix GTX, G8 FIREHAWK, Camaro SS and the LT1 powered Firebird/Trans Am WS6 and that is quite an extraordinary combination and it is even more impressive when you consider the Ford and Chrysler additions to the SLP lineup. This outstanding combination should lead to continued success with an opportunity for the two brands to work together giving them even more access to both innovative minds and outstanding ideas yet maintain their individuality. If you just take a brief look at the potpourri of products on the LMPERFORMANCE web site by SLP you will see exactly what we are talking about when we say this is a company you can trust to meet your high performance needs.
Reviews for SLP Performance 31067 (the item on this page) are show below.
99 T/A ls1 loudmouth II, Date: 4/26/2013
Ownership: more than 1 year
Wasnt sure weather ta get tha lm 1 or 2 so ta stay sound ordinence safe and I have no complaints. Its loud super aggressive and deep. I have tha cats removed and 1 loudmouth II that "y's" into 3 1/2 tips and its deep. Very satisfied but im changing to the loudmouth 1 because I want stupid loud lol. But if you want a good deep agressive muscle car sound thats just loud enough tha loudmouth 2 is tha way to go!!!
Slp cold air kit computer tune built transmission cat delete
Reviews for SLP Performance's Other products are show below.
SLP CAI, 160 deg. thermos, competition harmonic balancer,4L60E shift kit, 3400 rpm stall converter, 373 rear end gears, granatelli 85mm maf ,Diablo predator reprogram, dual exhaust.224/224/581/581 comp cam with 114lsa and dual springs.
K&N intake, magnaflow muffler swap, SLP rear section (resonator delete) and BlackBear Tune
First mod with opened up fog light surrounds to improve air flow.
These are parts that other customers have purchased while purchasing the product on this page.
Below are other popular parts other customers have purchased for their Pontiac Firebird, Formula, Trans Am.
* Shipping Notes: Please note FREE Shipping refers to shipping within the contiguous continental US. All other locations extra. If your order will be delayed, you will be notified via email the estimated shipping date.^