Pypes Off-Road X-pipe (99-04 GT)

Pypes Off-Road X-pipe (99-04 GT)
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Hey everyone, I’m Justin with and this is our power pack bolt on build up series, for all 99-04 Mustang GTs. With this power pack, we’ve put together some products that we feel are great first time mods, that would give any 99-04 GT a serious boost in power. So we’re going to get a quick baseline run, then hand our GT over to the crew so they can get started installing our power pack. Hey what’s going on Mike? Mike: Hey man, nothing, just finished the installation of our mods and we’re about to make another Dyno run. Justin: Very nice, yeah it looks good under here, what you got installed under the hood? Mike: Well first we installed Airaid cold air intake kit that comes with a high flow reusable air filter, so you never have to replace it. The Airaid’s going to increase air flow for the engine and allow it to breathe better and make more horsepower and it’s also going to help on fuel efficiency. Justin: Yeah, if you can stay off the pedal, right? Mike: Yeah. Justin: I see we’ve also got the BBK installed, what’s up with that? Mike: This is the one piece throttle intake, that features the throttle body and the plenum, that way you can have a bigger throttle body and not worry about restricting the air flow with a factory plenum. Justin: Mike, I know with this generation and these mods, we shouldn’t really need a tune right? Mike: Right, we don’t require a tune, but we are going to install a Bama performance custom tune, just to kind of tie everything together. Especially on our automatic, it’s going to help with our shift firmness, our shift points, and overall. Justin: That’s awesome, I know in conjunction with these mods we also have the Pypes off road X pipe going on, along with that Flowmaster American Thunder series Catback as well, what kind of numbers are you expecting from all these mods? Mike: We should expect to see about 20-25 horsepower. Justin: Sounds good to me man, you ready to do another run? Mike: Absolutely, let’s do it. Justin: So our baseline run on our automatic 2000 GT gave us 222 horsepower and 260 ft/lbs of torque, with our powerpack installed, we made 249 horsepower, and 295 ft/lbs of torque, giving us a peak gain of 27 horsepower over our baseline numbers and gains of 35 horsepower and 54 ft/lbs of torque throughout the curve. So as you can see we’ve just finished off our second Dyno run and we’re definitely happy with the results, the best part is all these mods are installed easily in just a few hours using basic hand tools. Now let’s get our GT off the Dynojet and onto the streets, so we can hear that Flowmaster in action, and see what these mods did for our motor. Alright, now we’ve got our GT out of the shop and onto the streets and been able to put it through its paces a little bit, it’s easy to see why these bolt ons are such a popular first choice with so many Mustang owners out there, especially these 99-04’s. Those bolt ons really woke up our 2 valve motor, especially when paired with our Bama tune, which has really firmed up our shifts as well. So be sure to check out some of our other 99-04 bolt on build ups where we improve our handling, work on our acceleration, and dress up our GT a little bit.

About Pypes

Pypes Performance Mustang Exhaust
Pypes Performance Exhaust offers a comprehensive product line for Ford Mustangs that includes Headers, Full Systems, Cat-Back Systems, Axle-Back Systems, X-Pipes, Mufflers and Tips. Their innovative Mustang products are fabricated using stainless steel materials that will provide their owners with long term service and satisfaction……and, Pypes products are backed by their limited lifetime warranty!
OUR PRICE$194.99
Market Price $216.99You Save 10% ($22.00)
Item # 20004
(4.0/5)95 Reviews
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Add Pypes High Flow Ceramic Catalytic Converter Kit
Add 2x MIL Eliminators

Product Features

  • Balance out exhaust gases for more power
  • Raspy Race Car Growl
  • Pypes modular construction
  • For off-road track use
  • 2.5" 409 stainless steel tubing
  • Fits 1999-2004 GT Mustangs
Balances Exhaust Gases. Pypes Off Road X-Pipe is second to none when it comes to balancing out the gas pressures in your exhaust system. This Pypes off road x-pipe creates more power and torque than a traditional H-pipe. Why? Because the exiting exhaust pulses are merged at the "X", resulting in less exhaust back pressure for more power.

Race Car Growl. This free flowing Pypes x-pipe for the 1999 to 2004 GT's not only increases power, but it also adds a raspy, race car growl to the sound of your exhaust with its modern "X" crossover pipe design.

Modular Construction.   Pypes unique three piece modular construction makes it quick and easy to add or remove a catalytic converter to your exhaust system in just minutes depending on your driving needs.

Durable Stainless Steel Construction.   Pypes uses sturdy 16 gauge 409 stainless steel mandrel bent 2.5" tubing for improved flow and features welded reinforcement plates for additional strength.

Application. This Pypes Off-Road X-pipe is designed to be a direct bolt-on for the 1999 to 2004 4.6L V8 GT Mustangs with either aftermarket short tube headers or the stock factory manifolds installed. Intended for off-road, track use only, does not include catalytic converters.

Technical Note: 2004 model year Mustangs will require the use of 18" O2 sensor plug-in extender wires!

Mid Pipe Specifications
Style Mid Pipe: Standard length "X" Type Headers Required: Shorty
Piping Material: 409 Stainless Steel Piping Size: 2.5"
Catalytic Converter: "No" - For off-road use only Fitment: 1999-2004 GT Mustangs

Installation Time:

(approx) 2 Hours

Difficulty Level:

Advanced mechanical skills required.

What's in the box?

Hardware included:
  • (2) 2.5" clamps

What's in the box?

Hardware included:
  • (2) 2.5" clamps
  • GT 99, 00, 01, 02, 03, 04
Known Exceptions:
Fits GT Only

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