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Kooks 1-5/8 in. Header and Catted X-Pipe Combo (99-04 GT)

Market Price $1,880.58 You Save 10% ($188.05)
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  • Item 65530
  • MPN#11212000


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    Features & Details

    • Increase Rear Wheel Horsepower and Torque
    • Includes Long Tube Headers w/ Matching Catted X-Pipe
    • 304 Stainless Steel Construction
    • High Flow Catalytic Converters
    • Free Flowing Mandrel-Bent Tubing
    • Fits 1999-2004 GT and Bullitt Mustangs
    Improve Horsepower And Torque. The Kooks Long Tube Header and Catted Shorty X-pipe combo kit for the GT and Bullitt Mustang will balance out the exhaust pressure to increase flow over the restrictive factory exhaust system resulting in more horsepower, torque, and better throttle response.

    Quality Construction. Manufactured from 1-5/8" mandrel bent 304 stainless steel tubing Kooks Long Tube Headers are TIG welded for strength, and feature a leak-free ball flange design to fit perfectly into the included 2.5" diameter 304 stainless steel Shorty X-pipe for excellent exhaust flow and performance.

    Natural Finish. These Kooks Headers feature a natural stainless steel finish, which provides an aggressive appearance to your engine bay. This is not a heat-resistant coating, AmericanMuscle recommends the use of Exhaust Heat Wrap for high performance applications.

    Recommended Upgrade. To realize the full power potential that this Kooks Long Tube Header and X-pipe Kit has to offer, AmericanMuscle recommends a custom tune with a Mustang Handheld Tuner to reprogram the vehicles computer (ECU) for proper operation.

    Application. This Kooks Long Tube Header and matching catted shorty X-pipe combo kit is designed specifically for the 1999-2004 4.6L GT and Bullitt Mustangs.

    Technical notes. Not legal for use on pollution controlled motor vehicles; intended for off road use only.

    Fitment: 1999 2000 2001 2002 2003 2004 Details

    What's in the Box
    • Kooks Long Tube Headers
    • Matching Kooks catted shorty X-Pipe
    • Necessary Gaskets
    • O2 Extensions
    Installation Info
    Tech Specs
    Header Specifications
    Header Type: Long Tube Finish : 304 Stainless steel
    Type Mid Pipe Required: Kooks Shorty X Fitment: 1999-2004 GT and Bullitt

    Mid Pipe Specifications
    Style Mid Pipe: Shorty "X" Type Headers Required: Kooks Long Tube
    Piping Material: 304 Stainless Steel Piping Size: 2.5"
    Catalytic Converter: "Yes" Fitment: 1999-2004 GT and Bullitt
    Will it fit my Mustang?

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    6 Questions / 6 Answers

    Ask a Question

    will these headers require a oil filter relocation? and if i ever need to change the spark plugs after i install these headers, will i need to remove the headers to replace the spark plugs?


    • The Kooks 1-5/8 in. Header and Catted X-Pipe Combo will not require the oil filter to be relocated and you would be able to replace the spark plugs with the headers installed.


    Helpful (0)

    If i have buy this combo would it hinder the emmisions for CA?


    • The Kooks 1-5/8 in. Header and Catted X-Pipe Combo will not be Carb approved for use in California.


    Helpful (0)

    Will this product work on the borla atak series?


    • The Kooks Header and Catted X-Pipe Combo will work with and Catback designed for the 1999-2004 Mustangs

      Rob D

    Helpful (0)

    is this combination applicable for borla stingers catback?


    • This combination will be able to work with the Borla Stinger catback exhaust as the piping size is 2.5" and the flanges will mate up to one another.


    Helpful (0)

    Ive herd that puting a 3" piping on a stock 02 gt i would lose power unless i have more mods i judt want to know if that is true?


    • Putting an exhaust with a diameter too large will decrease back pressure and cause a loss of low end power. This set of 1 5/8inch headers is perfectly fine for naturally aspirated engines.


    Helpful (0)

    will these work with an automatic transmission?


    • yes it would


    Helpful (0)

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    Customer Reviews (2) Write a Review

    Overall Rating 5.0

    out of 5 stars

    Installation Time:Weekend

    Installation Cost:$250-$500

    • Loudness / Volume 5 5
    • Exhaust Note 4.5 4.5
    • Fit & Finish 4.5 4.5
    • Bang For Your Buck 4.5 4.5

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      July 14, 2017


      These pipes sound so freaking good at about 3k rpms would definitely recommend for anyone that likes a loud car lol


      Year: 2001 Submodel: GT

      Helpful (6)

    • 5/5

      Installation Time: Afternoon

      June 18, 2016

      Great Headers

      Great headers, Brought my car from a mumble to a rumble in a matter of hours (Self Installed) I'm glad to open my bonnet and see that shiny chrome.


      Year: 2001 Submodel: GT

      Helpful (7)

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