1990-00 GM Class A Motorhome (4L80E transmission only)
366-454 Big Block V8 (with smog fittings)
Header Style: 4:2:1 Long Tube Tri-Y Headers
Finish: Silver Ceramic Coated
Weld Up: Yes, Y-pipe outlet must be welded to exhaust system
Primary Tube Diameter (in): 1-3/4"
Primary Tube Gauge: 14 Gauge
Collector Attachment: 3-Bolt Flange
Collector Diameter: 2-1/2"
Flange Thickness: 3/8"
Bolts and/or Studs Included: Yes
Gaskets Included: Yes
Reducers/Adapters Included: No
Y-Pipe (Crossover) Included: Yes
Y-Pipe Inlet Diameter: 2-1/2"
Y-Pipe Outlet Diameter: 3"
Catalytic Converter(s) Included: No
Quantity: Sold as a Complete Kit
CARB E.O. #: D-540-5
Warranty: Limited Lifetime to original purchaser
Unless otherwise noted, these headers are designed to fit the vehicle as it came from the manufacturer. This includes components like cylinder heads, chassis, steering, motor mounts, body mounts and bushings, etc. If your vehicle is using aftermarket components, parts from other applications, or custom altered parts, then it is the installer's responsibility to verify fitment
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