1970-74 Pontiac Firebird, Including 455SD, Dual In/Out Transverse Muffler

1970-74 Pontiac Firebird, Including 455SD, Dual In/Out Transverse Muffler


Our mufflers are a double walled shell. The end caps are roll-seamed. The outer wrap is smooth with no exposed welds. The baffles and end caps are a heavy gauge material.

  • Waldron’s has brought this muffler back to provide a close match to the original sound, enhanced flow rate from the original, while maintaining the OE look and size. The interior design is derived from the OE Pontiac part. Muffler cavities are packed with sound absorbing materials to compensate for the increased sound levels created by the larger interior diameters. The muffler dimensions are; 4.75 inches X 9.75 inches oval cross-section. The case is 22.75 inches in length with an over-all of 27.75 inches.
  • All mufflers are built to the OEM specs. Our Mild Impostor's and Impostors allow you to keep your vehicle stock while changing your exhaust notes. Our Mild Impostor is a middle of the road turbo muffler, designed to give your exhaust a deeper, throatier tone. Our Impostor is a high performance, aggressive turbo muffler.
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  • Our exhaust systems are made to order. For our current lead time, please refer to the gray banner above.
  • For orders shipping within the 48 USA contiguous states, the shipping charges will calculate correctly. For orders shipping outside the 48 USA contiguous states, please submit your order without payment, we will get in touch with you with your shipping options and get your order completed.
  • The following statement pertains to pipes only (mufflers have a 1 year warranty regardless of material chosen) and to vehicles that are not daily drivers and are stored in an enclosed building: Aluminized Steel has a life expectancy of 20-25 years and is considered to be truer to the original material on vintage vehicles. T409 Stainless Steel is ferric and magnets will stick to it. T409 stainless steel is the same type of stainless used by car manufactures today and will never rust through, although it may develop pock-marks of rust which can simply be buffed out.
  • When building our exhaust systems; where (or if) it requires a pipe diameter of 2” or larger, it will be 14-gauge tubing, where (or if) it requires a pipe diameter smaller than 2”, it will be 16-gauge tubing.
  • Check out our On-line Swap Meet for both aftermarket and OEM (some) H pipes and Y pipes, along with “odd ball” mufflers.



Additional information


Aluminized Steel, T409 Stainless Steel


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