Home / Shop / Flowmaster Stainless Steel American Thunder Exhaust Systems 817412 System, Thunder, Header-Back, Steel, GM A Body, Kit

Flowmaster Stainless Steel American Thunder Exhaust Systems 817412 System, Thunder, Header-Back, Steel, GM A Body, Kit

SKU: FLO817412

Exhaust Systems

Flowmaster

Flowmaster Stainless Steel American Thunder Exhaust Systems 817412 System, Thunder, Header-Back, Steel, GM A Body, Kit

SKU: FLO817412

Exhaust Systems

IN STOCK! Est Ship 4-7 days. This item is IN STOCK at one of our warehouses or distribution centres, the ETA is the approximate time required to prepare your order for dispatch.

We accept

Description

Flowmaster Stainless Steel American Thunder exhaust systems have been designed with the latest exhaust technology available. Through this technology, you will experience improvements in acceleration, passing power, and fuel mileage. The key to these performance improvements is Flowmaster's use of mandrel-bent tubing. Their tubing allows for superior exhaust gas flow, while their stainless steel construction allows for their corrosion-resistant qualities. These American Thunder exhaust systems also feature a stainless steel muffler(s) that'll give you plenty of Flowmaster sound.

Part Type

Exhaust Systems

Data: v4.2 - Upd: 2026-10-16 04:09:17

Specifications

Product Attributes - Brand: Flowmaster
Product Attributes - Manufacturer's Part Number: 817412
Product Attributes - Part Type: Exhaust Systems
Product Attributes - Product Line: Flowmaster Stainless Steel American Thunder Exhaust Systems
Product Attributes - UPC: 700042024025
Product Attributes - System Material: 409 stainless steel
Product Attributes - System Style: Header-back
Product Attributes - Exhaust Type: Dual
Product Attributes - Exit Location: Rear
Product Attributes - System Finish: Natural
Product Attributes - Catalytic Converter(s) Included: No
Product Attributes - Intermediate Pipe Diameter (in.): 2.50 in.
Product Attributes - Muffler Included: Yes
Product Attributes - Muffler Quantity: Two
Product Attributes - Muffler Configuration: Single inlet/Single outlet
Product Attributes - Muffler Style: Chambered
Product Attributes - Muffler Material: 409 stainless steel
Product Attributes - Muffler Finish: Black
Product Attributes - Hardware Included: Yes
Product Attributes - Tailpipe Diameter (in.): 2.50 in.
Product Attributes - Tip Included: No
Product Attributes - Remanufactured: No
Product Attributes - Quantity: Sold as a kit.
Product Attributes - Notes: Due to variations in different manufacturers headers, modifications to the length and or angles of the intermediate pipes may be required when connecting to the header collectors.
Product Attributes - Special Attention: It is illegal to install parts or components that bypass, defeat, or render inoperative the manufacturers’ technology and design necessary to reduce vehicle emissions to meet state and federal Clean Air Act standards.

Reference Information

Brand Name/s	Flowmaster
StreetFX SKU	flo817412
SFX Item ID	4983905
Supplier Item Code	4983905
Manufacturer SKU	817412
Manufacturer UPC	700042024025
Alternative References	FLM817412

Compatibility

Application Data

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Small Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Small Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Small Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; U/K; LT Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; U/K; LT Swap
Region	United States (USA)
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; U/K; LT Swap
Region	United States (USA)
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Big Block Chevy Swap
Region	United States (USA)

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	V8
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	HOLIDAY
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, LS Swap
Region	United States (USA)

Make	PONTIAC
Model	GTO
Submodel	HOLIDAY
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; U/K; LT Swap
Region	United States (USA)
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	HOLIDAY
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; U/K; LT Swap
Region	United States (USA)
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	HOLIDAY
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; U/K; LT Swap
Region	United States (USA)

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, LT Swap
Region	United States (USA)
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, LT Swap
Region	United States (USA)
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; U/K; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Wagon
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; U/K; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; U/K; Small Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; U/K; Small Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1965
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Automatic
Drivetrain	RWD
Application Notes	RWD; Transmission; Small Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1966
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Big Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1966
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; U/K; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, Big Block Chevy Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1966
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, LT Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	X

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1966
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, LT Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

Make	PONTIAC
Model	GTO
Submodel	CUSTOM
Beginning Year	1966
Ending Year	1966
Engine Type	L6
Liter	6.4
CID	389
CC	6376
Engine Size	6.4L/389
Engine Family	Pontiac V8
Body Style	Standard Cab Pickup
Transmission	Manual
Drivetrain	RWD
Application Notes	RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Transmission; 2.5" Stainless Steel Pipes, Aggressive to moderate sound, LT Swap
Region	United States (USA)
Truck Bed Length in. (AAIA)	78.5in, 199.4cm
Engine VIN Code	Y

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Flowmaster Stainless Steel American Thunder Exhaust Systems 817412 System, Thunder, Header-Back, Steel, GM A Body, Kit

Flowmaster Stainless Steel American Thunder Exhaust Systems 817412 System, Thunder, Header-Back, Steel, GM A Body, Kit

Description

Part Type

Specifications

Reference Information

Compatibility

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