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Flowmaster 40 Series™ Muffler 425403

Flowmaster 40 Series™ Muffler 425403
Flowmaster 40 Series™ Muffler 425403Flowmaster 40 Series™ Muffler 425403Flowmaster 40 Series™ Muffler 425403
$152.99 ea
NEWARRIVING SOONEstimated Ship Date 10/16/2023 (If Ordered Today)180 available from HOLLEY PERFORMANCE PRODUCTS as of 09/23/2023
Model: 4005043
Supplier has not provided any fitment data for this product.
The original Flowmaster series muffler delivers an aggressive exterior and interior tone. If you're looking for that original Flowmaster sound this is the muffler is for you. Constructed of 16 gauge aluminized steel and fully MIG welded for maximum durability.
  • Durable Fully Welded 16 Gauge Aluminized Steel
  • Aggressive Sound Exterior Exhaust Tone
  • Noticeable Interior Resonance
  • Excellent Street/Strip And Off Road Application
Holley Performance Emission Code 5: This part is legal for sale or use on Emissions Controlled Vehicles; Uncontrolled (Non-Emissions Controlled) Vehicles; and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations
Installation Notes:
Universal Muffler - Some adaptation may be required.
About Flowmaster

Manufacturer of performance exhaust systems, mufflers, performance air intakes, turbo boost modules, catalytic converters, race mufflers, headers and numerous exhaust accessories for late model cars, trucks, off-road, Jeeps, SUV’s, classic muscle cars, powersports vehicles and more. Flowmaster® gives you lots of exhaust choices with 12 designs of chambered mufflers, 3 styles of our exclusive “laminar-flow” mufflers and a new line of FlowFX “straight-through” performance mufflers, along with 5 sound categories of exhaust systems, giving you the customer, the power to custom tailor the sound of your vehicle whether you prefer mild, moderate or aggressive tones and sound levels. Since 1983, Flowmaster is the company you can trust, and has led the industry in offering only the best products you can buy for your vehicles.


Download Name File Size


Automotive Item Grade High Performance
Body Height (in) 4
Body Length 13.000 in.
Body Length (in) 13
Body Width (in) 9.75
California Proposition 65 Required No
Color Black
Emission Code 5
Finish Painted
Fitment Universal
Inlet Connection Type Clamp-On
Inlet Diameter (in) 2.5
Inlet Inside Diameter 2.500 in.
Inlet Outside Diameter 2.500 in.
Inlet Position Dual
Inlet Quantity 2
Material Aluminized Steel
Muffler Body Height 4.000 in.
Muffler Body Length 13.000 in.
Muffler Body Shape Oval
Muffler Body Width 9.750 in.
Muffler Inlet Diameter 2.500 in.
Muffler Outlet Diameter 3.000 in.
Muffler Overall Length 19.000 in.
Muffler Series Original 40 Series
Muffler Type Reflection
Outlet Connection Type Clamp-On
Outlet Diameter (in) 3
Outlet Position Center
Outlet Quantity 1
Outlet Type Single Center
Overall Length 19.000 in.
Overall Length (in) 19
Part Type Exhaust Muffler
Reversible No
Shape Universal
Sound Level Aggressive
Tip Quantity 0
Type of Muffler Chambered
Vehicle Type Classic Muscle Car
Warranty Time 36 Months


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Flowmaster 40 Series™ Muffler 425403:
Mustang Depot 2023