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Vehicle Info NeededFLOWMASTERPART NUMBER: 389-842580
80 Series Cross-Flow Muffler 2.5 in. In/Out (Same Side Out)
Color:
$18895
3 left in stock
Ships on Sep 08, 2026
Lowest Price GuaranteeIn/Out Same Side Out
80 Series Cross-Flow Muffler2.5 in. In/Out (Same Side Out) Case: 9.5 in. L (4 in. Thick) Overall: 13 in. Length x 9.5 in. Width Stainless Steel
Note:
- Universal Muffler - Not a direct fit. Some adaptation required.
True Dual Performance
Flowmaster's 80 Series Cross-Flow Mufflers offer true dual performance where only a single exhaust system will fit, commonly found on classic Camaros and Firebirds. The 80 Series Cross-Flow Muffler fits transversely behind the rear axle and in front of the fuel tank making it the perfect OE replacement. The 80 Series gives excellent ground clearance, aggressive tone and increased power output over stock.
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Features:
- True dual performance
- Aggressive tone
- Stainless steel or aluminized steel
- Fully MIG-welded
- Single or dual outlets
- Perfect replacement for Camaro/Firebird configuration
Part TypeMuffler
Product LineFlowmaster 80 Series Cross-Flow Mufflers
BrandFLOWMASTER
Package Height4.5
Package Width10.0
Package Length20.5
Weight10.8 PG
Part CategoryPerformance Parts
ShapeOval
Exhaust Tip Quantity0
Outlet Quantity1
Inlet LocationOffset
Muffler TypeChambered (Transverse)
Inlet PositionCenter
Inlet TypeWeld-On
Inlet Size (In.)2.5
Heat Shield AttachedNo
Mount TypeUses New Hangers (Not Included)
Body Length13 in.
Muffler Count1
Inlet Outside Diameter2.63 in.
Inlet Diameter2.50 in.
Clamps IncludedNo
Inlet Quantity1
Sound LevelAggressive
FinishHigh-Temperature Paint
Outlet Outside Diameter2.63 in.
ReversibleNo
Universal Or Specific FitUniversal
Outlet Size2.5 in (63.5 mm)
Hanger IncludedNo
Inlet Connection TypePipe Connection
ColorBlack
Muffler Series80 Series Crossflow
TunableNo
Overall Length20.50 in.
Material409 Stainless Steel
Body Width9.50 in.
Outlet Inside Diameter2.50 in.
Body Material409 Stainless Steel
Inlet Inside Diameter2.50 in.
Outlet LocationOffset (Same End)
FitmentUniversal
Body Height4 in.
Outlet TypeDual Outlet
Part FitmentUniversal
Outlet PositionDual Rear
Vendor Part Number842580
Package Qty1
Package TypeEA
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