Aggressive Sound. Let them know you're coming with the Flowmaster 40 Series Offset/Offset Oval Muffler. With its generous 3-inch body diameter, this exhaust upgrade delivers a more aggressive (though still street-legal) exterior tone and a noticeable interior resonance that will have you feeling (and hearing) the true power of your 'Stang.

Increases Torque/Horsepower. Is your stock muffler robbing your 'Stang's performance? The two-chamber, precision-deflector design of the Flowmaster 40 Series Muffler supercharges your exhaust, giving you a marked increase in torque and horsepower.

Tough Construction. The Flowmaster 40 Series Offset/Offset Oval Muffler is crafted from durable 16-gauge aluminized steel and is completely MIG-welded for the ultimate in strength and durability. 40 Series Mufflers also don't have any packing, so there's nothing to blow out.

Cut & Clamp Installation. Flowmaster makes it easy to install the 40 Series Muffler. With the proper clamps and hangers (not included), installation should take you less than two hours.

Application. The Flowmaster 40 Series Oval Muffler is built specifically to fit all 1979-2004 Mustangs, excluding 1999-2004 Cobras.

Fitment: 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Details