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BBK Competition Series Off-Road X-Pipe (99-04 4.6L)

Item 56130
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    Product Information

    Features, Description, Reviews, Q&A, Specs & Installation


    • Improves Exhaust Flow and Sound
    • Raspy Race Car Growl
    • 2-1/2" Mandrel-Bent Aluminized Tubing
    • For Off-Road, Track Use
    • Fits 1999-2004 GT, Bullitt, Mach 1, and SVT Cobra


    Increases Overall Performance. Add even more horsepower and torque to the rear wheels by eliminating those power robbing catalytic converters with a BBK Off-road X pipe. A BBK X pipe will greatly improve your pony's exhaust flow to increase overall performance and sound.

    Race Car Growl. A free flowing BBK x-pipe not only increases power, but it also adds a crisp raspy, race car growl to the sound of your exhaust with its modern "X" crossover pipe design.

    Durable BBK Construction. This BBK direct replacement X-pipe features 2.5” diameter CNC mandrel bent aluminized tubing and a merged X crossover to improve exhaust flow. Additional features include factory O2 sensor locations, and OEM style die-stamped flanges all to ensure a perfect fit.

    Application. Specifically designed to fit the 1999 to 2004 4.6L Mustangs, including the GT, Bullitt, Mach 1 and SVT Cobra. This Off-Road X-pipe is a direct fit replacement for the stock mid pipe.

    Technical Note. This BBK product is not legal for use in emission restrictive states.

    Fitment: Details

    CA Residents: WARNING: Cancer and Reproductive Harm -


    Customer Reviews (100+)

    Write a Review

    Ratings Summary

    4.5 out of 5 overall rating from 100+ customers

    Installation Time: Afternoon

    Installation Cost: $100-$250

    • May 18, 2019

      5 2003 GT - jgotjuice Installation Time: Less than 1 Hour

      Perfect fit

      Easy and quick to install and it’s a way better upgrade from stock if you’re looking to improve the sound of your 99-04 mustang

      Helpful (0)
    • March 20, 2019

      5 2003 GT - Shane Installation Time: Shop Install


      Love the sound with a loudmouth 2 exost. Recommend

      Helpful (0)
    • March 15, 2019

      5 2003 Mach 1 - TimS Installation Time: Full Day

      Tim s

      Very good product by bbk mounted up great with bbk headers amazing upgrade sounds good highly recomend this paired with bbk header

      Helpful (0)
    • March 05, 2019

      4 2004 GT - JRomero Installation Time: Afternoon

      AWESOME SOUND!! But rear O2 will not reach.

      I paired the O/R x-pipe with a flowmaster catback exhaust on my 04 GT. Thing sounds insane. Since it doesn’t have cats, you will not need the rear O2 sensors. Just plug up the empty bungs and you’re good. Only issue with that is, you will get a check engine light. To resolve that, you’ll need MIL eliminators so the check engine light won’t come on. Another issue with that, the O2 bungs are further back on the x-pipes than the stock h-pipe so O2 sensors plus MIL eliminators ARE NOT going to reach. (Ask me how I know). You’ll probably need to daisy chain the O2 sensors, MIL eliminators plus some O2 sensor extensions in order for the wiring to reach.

      Helpful (0)
    • March 01, 2019

      5 2003 Mach 1 - AveryG

      Quite loud... But quite awesome

      I paired this BBK o/r x-pipe with the SLP Loudmouth 1 axle-back I had on my Mach 1, and the difference in sound is huge. The lack of catalytic converters makes the volume increase quite a lot, and the x-pipe design makes it very raspy as soon as you hit 2000RPM. The combination of those two things makes a godly sound that's intoxicating. I just wanna go over some things so you know what you'd be getting into... Like I said, because there's no cats, the volume increases by like, double what it would normally be, especially if you've got an axle-back exhaust like the SLP Loudmouth which is very unrestrictive, so it was already loud to begin with. I wouldn't recommend buying this if you don't want an absurdly loud exhaust, or if you daily your mustang (unless you're okay with it!) The x-pipe makes things raspy and, depending on your exhaust, possibly a bit "trumpety". Basically, your mustang won't growl so much as it will wail loudly! A lot of people like this, a lot don't, so look up videos on Youtube to help give you an idea of how yours will sound. And lastly, because of how, let's say "ineffecient" the 4.6 modular is, it has a tendancy to have a lot of unspent fuel flying into the exhaust, which causes popping and crackling sounds, which I'd think most people like. By having an x-pipe with no cats combined with an unrestrictive exhaust, your 4.6 turns into a freakin' popcorn machine! At around 3000rpm or higher, when you let off the gas, you will make people's head turn with absurd amounts of loud pops and snaps. It's an absolute blast... If this all sounds great to you, go for it, it's one of the best things you can buy for around $200.

      Helpful (1)
    • January 18, 2019

      5 2000 GT - NickC Installation Time: Less than 1 Hour

      Sounds awesome!

      I had no issues. Sounds great. All the welds were great. It paired right up with my exhaust. Couldn’t be happier

      Helpful (4)
    • January 05, 2019

      5 2003 Mach 1 - Justin Installation Time: Afternoon

      03 mustang Mach 1

      Definitely a awesome product sounds amazing with slp loudmouth 1 neighborhood doesn’t like it but I do lol

      Helpful (5)
    • November 29, 2018

      5 2002 GT - AntonioP Installation Time: Less than 1 Hour

      Sounds amazing

      Great product. Completed the sound and loudness of my 2 valve.

      Helpful (3)
    • November 23, 2018

      5 2004 GT - LouanneV Installation Time: Afternoon

      BBK xPipe

      Everything needed was in the box and it bolted on with little fanfare, just needed to go to the parts store locally for one gasket for head pipe passengers side that didnt come with the kit. No biggie it was nine bucks. Added a growl to my car!

      Helpful (3)
    • November 19, 2018

      1 2000 GT - DarrenB Installation Time: Afternoon

      Too raspy

      When it says raspy it means raspy. Even in the normal driving range it sounds tinny like your dragging cans behind your car. I wouldn’t recommend and will probably put the stock h pipe back on.

      Helpful (5)

    Questions & Answers (55 answers)

    5 Top Rated Questions

    Would I be able to weld my catalytic converters onto this x pipe to make it smog legal?

    • You would be unable to weld the OEM cats to the BBK Off-Road X-Pipe. This would constitute modifying the emissions equipment causing a failure for smog testing.

    Helpful (1)

    Will I get a CEL? By putting this o/r x-pipe on will I get any CEL's because with this I'll have no cats. Thank you

    • Yes you will, if you buy some plug in mil eliminators it will fix your problem or if you have a tuner you can shut the codes off

    Helpful (1) Show 2 more answers

    can this be used as shorty x-pipe later on ? my current exhaust setup is stock headers and stock h-pipe paired with flowmasters. I've been thinking about getting this x-pipe for a long time but my only concern is that at some point later on, i will be getting bbk long tubes (money willing) and I'm not sure if i can then just simply remove the 2 extension arms that connect the X figure in the pipe to the factory headers and re-use the x-pipe (which would technically be bbk's shorty x-pipe) with my long tube headers ? I looked at both bbk's shorty and normal x-pipes and the only difference i could find was the 2 extension pipes (how ever i could be wrong).

    • Unfortunately not. The tubing lengths on this off-road mid-pipe are not the same as the shorty mid-pipe and therefore, they can not be interchanged. If you switch from stock headers to the long tubes later on, you will need to purchase the shorty mid-pipe at the same time for proper fitment.

    Helpful (1) Show 1 more answer

    does this bbl off-road x-pipe eliminate the cats

    • Yes, this x-pipe will delete the cats.

    Helpful (0)

    Will this bolt right up to a factory stage 2 roush side pipe exhaust? Trying to find options for my girlfriends roush. Hard to find direct fit options for those cars.

    • That's a great setup! This will absolutely fit with it.

    Helpful (0)
    10 More Questions
    Will this work with BBK Shorty Headers ? 1 answer
    Do I need 02 sensor extensions for this X-pipe? 1 answer
    Will this x pipe fit an automatic transmission? 1 answer
    I have already slp on my car and i want to install the off road x pipe is it legal in AZ? 1 answer
    Will this work with the bbk shorty headers that I currently have installed? I’m running bbk shorty headers, stock H pipe and magnaflow after the H pipe 1 answer
    If i have a side exit exhaust, would i have to run my pipes through the back if i buy this? 1 answer
    Do you need to buy a new gasket to use this? 1 answer
    How loud would these be on a gt with flowmaster 40s? 1 answer
    will the x-pipe section align to my factory cat pipes? looking to cut oem pipes to preserve cats for now and clamp to the new x-pipe. 1 answer
    My 02 GT already has ground clearance issues because it is lowered. Will this x-pipe create more issues due to clearance? Or will this be better with ground clearance over the stock H pipe? 1 answer

    Installation & What's in the Box

    Installation Info

    What's in the Box

    • (1) Off-road X-pipe
    • (2) Down Pipes
    • (4) Bolts
    • (8) Flat washers
    • (4) Lock washers
    • (4) Nuts

    Tech Specs

    Mid Pipe Specifications
    Style Mid Pipe: Standard length "X" Type Headers Required: Shorty or Stock Manifolds
    Piping Material: Aluminized Steel Piping Size: 2.5"
    Catalytic Converter: No - Off-Road Use Only Fitment: 1999-2004 GT, Bullitt,
    Mach 1, Cobra

    Will It Fit My Mustang

    • Bullitt - 01
    • Cobra - 99, 01, 03, 04
    • GT - 99, 00, 01, 02, 03, 04
    • Mach 1 - 03, 04

    2000 GT Mustangs may require modification to stock manifold studs for proper fitment

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