Borla® - Boomer™ Rock-It Stainless Steel Round Race Muffler

Borla® - Boomer™ Rock-It Stainless Steel Round Race Muffler Borla® - Boomer™ Rock-It Stainless Steel Round Race Muffler Borla® - Sound Information Borla® - Exhaust Systems Sound Level Introduction on Dodge Challenger R/T Borla Authorized Dealer
Item Number: 470366
Availability: In Stock
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Universal Boomer™ Rock-It Stainless Steel Round Race Muffler by Borla®, 2.25" Inlet, 6.75" Thick x 6.75" Wide x 14" Case Length, and 4.5" Side Round Tip. Upgrade the looks, performance and sound of your ride with just a muffler swap. These mufflers increase exhaust flow and horsepower, and they come fully polished with an exhaust tip already installed. They're made of durable austenitic stainless steel and warranted for one million miles.

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Product Details
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  • Improves exhaust flow for better performance
  • Increases horsepower 7-10%
  • Dyno and race proven
  • Pronounced exhaust tone
  • Patented straight-through muffler design reduces backpressure while absorbing sound waves
  • Made from the finest austenitic stainless steel for long-lasting durability
  • All welded construction
  • Fully polished with exhaust tip attached
  • Backed by the exclusive Borla Million-Mile warranty
  • Proudly made in the USA

Lose your stock muffler and get increased power and performance, awesome sound and great looks. The Boomer Rock-It Stainless Steel Round Race Muffler will improve exhaust flow, helping your engine make 7-10% more horsepower. The Boomer’s patented straight through muffler design reduces restriction and increases exhaust gas velocity, making sure each cylinder is completely evacuated to make room for the incoming charge. This design absorbs the sound waves without disturbing the power waves, in contrast to the chambered mufflers used by most aftermarket companies. Chambered mufflers use partitions or baffles to subdue sound waves, which also creates backpressure and reduces power.

Borla - Boomer Rock It Mufflers

But improved performance is only part of what you want in an aftermarket muffler, you also want great sound and head turning looks. There’s no need to worry with the Borla Boomer Rock-It. Borla has many years of automotive acoustical experience and the company is staffed with automotive enthusiasts just like you that listen and drive cars to make sure your muffler has the right sound to go with the power. The Boomer Rock-It has a definite “growl” that’s louder than stock without being irritating.

Borla uses austenitic stainless steel in the construction of the Boomer Rock-It muffler, which contains high levels of nickel and chromium, to resist corrosion. This material is harder than the lower grade stainless steel used by the OEM manufacturers, yet is very ductile. Nevertheless, the increased hardness requires special equipment to form and bend. The muffler contains a stainless steel perforated tube wrapped with several layers of stainless steel sound absorbing material and a layer of ceramic sound absorbing, high temperature material, all contained in a fully welded stainless steel shell. Then Borla goes the extra distance; they fully polish the muffler and install a polished 4.5” round exhaust tip, so you get great looks right out of the box.

Borla is so confident in the quality of this muffler that it’s guaranteed against defects in materials and workmanship for one million miles.

Brand: Borla       Part Number: 40058       UPC: 808422400589
paypal credit Borla Exhaust Systems

Borla® is the leading manufacturer of stainless steel performance exhaust products. The company began three decades ago making exhaust systems for concours classic Rolls Royce and Ferrari models, and gradually evolved to become the premier manufacturer of performance exhaust products for street, off-road and racing. Borla pioneered many improvements in the design of performance exhaust systems, holds several patents for innovative exhaust system technology, and has won numerous “Best New Product” awards. Today the company operates a state of the art research and development center in Oxnard, California, and makes all of its products at a world-class manufacturing facility in Johnson City, Tennessee.

Product Reviews (3)

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Borla® - Boomer™ Rock-It Stainless Steel Round Race Muffler
Borla® - Boomer™ Rock-It Stainless Steel Round Race Muffler
Average Rating:  4.8 of 5
| Posted by | (Grand Forks, ND)

Easy to install and great sound, I completely satisfied.

1 people found this review helpful.
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| Posted by | (Myrtle Beach, SC)

Good looking - Installed easily - Worth the money - Very good quality.

3 people found this review helpful.
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| Posted by | (Tijeras, NM)

Awesome deep sound... Great value. Received shipment days before it was supposed to get here. Recommended for anyone who wants something more than that cheap muffler sound.

7 people found this review helpful.
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