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American Racing Headers 1-7/8 x 3 in. Long Tube Off-Road Headers w/ X-Pipe - Long System (15-17 GT)

Market Price $2,262.99 You Save 13% ($295.29)
Our Price

$1,967.70 (kit)

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  • Item 389161
  • MPN# MTC5-15178300LSNC

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Features & Details

  • American Racing Headers Long System
  • Increases Rear Wheel Horsepower and Torque
  • Long Tube Header Design - 1-7/8"
  • X-Pipe Included - Eliminates Factory Resonator
  • 3" Mandrel-Bent Tubing (Steps Down to 2.5")
  • 304 Stainless Steel Construction
  • Intended for Off-Road, Track Use Only
  • Made in the USA
  • Fits Left Hand Drive Models Only
  • Fits 2015-2017 GT Mustangs with Factory or 2-1/4" Aftermarket Axle-Back
More Horsepower And Torque. An American Racing Headers Off-road 1-7/8" Long Tube Header and X-Pipe Long System is designed to increase the power and performance of your 2015-2017 GT Mustang. These American Racing Headers and X-Pipe kit will greatly improve your GT Mustangs exhaust flow, over the restrictive factory manifolds and resonator Mid Pipe, to significantly increase rear wheel horsepower and torque.

Race Car Growl. The included X-Pipe not only eliminates the factory resonator to help increase power, but it also adds a loud raspy, race car growl to the sound of your exhaust with its modern "X" crossover pipe design.

Quality Construction. American Racing Headers are manufactured in the USA from mandrel-bent 1-7/8" diameter 304 stainless steel tubing that merges into 3" collectors with scavenger spikes for superior exhaust flow. These long tube headers feature a one piece 3/8" header flange for additional strength, leak-free performance and an OEM style fit.

Required Upgrade. To realize the full power potential that these Long Tube Headers have to offer, AmericanMuscle highly recommends a Bama custom tune with a Mustang Handheld Tuner to reprogram the vehicles computer (ECU) for proper operation.

Cut & Clamp Installation. American Racing Headers designed their 3" Long Systems to "step down" at the rear axle, which allows you to reuse your factory mufflers or the 2-1/4" aftermarket axle-back of your choice. Installation will require cutting and reusing the factory muffler assemblies and clamping them in place. Clamps and detailed instructions are provided.

Application. This American Racing Headers 1-7/8 x 3 in. Off-road Long Tube Header with X-Pipe Long System is designed to fit both Fastback and Convertible 2015-2017 GT Mustangs equipped with the coyote 5.0L DOHC V8 engine. Requires the use of the factory or a 2-1/4" aftermarket axle-back exhaust for proper installation.

Technical Notes. Long tube headers are not legal for use on pollution controlled motor vehicles; they are intended for off road use only.These Headers are intended for left hand drive applications only.

Fitment: 2015 2016 2017 Details

What's in the Box
  • (1) Driver side header
  • (1) Passenger side header
  • (2) Off-road connection pipes
  • (1) X-pipe
  • (2) Intermediate pipes
  • (2) Header gaskets
  • (4) Oxygen sensor extension
  • (8) Clamps
  • (1) Bracket
  • (16) Bolts
Installation Info
Tech Specs
Header Specifications
Header Type: Long Tube Type Mid Pipe Required: Included
Material: 304 Stainless Steel Finish: Natural
Catalytic Converter: "No" - For off-road use only Fitment: 2015-2017 GT Mustangs
Will it fit my Mustang?
  • GT - 15, 16, 17

These Headers are intended for left hand drive applications only.

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1 Questions / 1 Answers

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I want to run a full and true 3 inch exhaust system using arh long sytems and to use flowmaster outlaws as my axel backs. Will the flowmaster axel back connect directly to the long system or will I need additional 3 inch under axel piping?


  • If you want to run a true 3" set up, the American Racing Headers Long Tube Off-road Headers w/ X-Pipe - 1-7/8 x 3 in. Long System (15-17 GT) will work in conjunction with the Flowmaster Outlaw Series Axle-Back Exhaust (15-17 GT) item #389966 ( as the American Racing Headers Long Tube Off-road Headers w/ X-Pipe will come with 3" flow tubes from the X-Pipe to the Axle-Back Exhaust.


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Customer Reviews (1) Write a Review

Overall Rating 5.0

out of 5 stars

Installation Time:Afternoon

  • Loudness / Volume 5 5
  • Exhaust Note 5 5
  • Fit & Finish 5 5
  • Bang For Your Buck 4 4

  • 5/5

    Installation Time: Afternoon

    October 04, 2016


    Just had these headers installed on my 2016 5.0 And from the first start up i've been In love. The stock headers are so restrictive and these really open the car up! They look great under the hood too!


    Year: 2016 Submodel: GT

    Helpful (2)

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