(approx) 2 Hours
Light to Moderate mechanical skill required.
- Customer Submitted:
- Magnaflow MagnaPack (99-04 GT / Mach 1 / Bullitt) - Installation Instructions
Hi I’m Justin with AmericanMuscle.com, and I’m taking a closer look at the Magnaflow Magnapack catback exhaust fitting the 99-04 Mustang GT and Mach 1. The Magnapack gets its name from these two Bullitt style mufflers, which are a throwback to the classic 60’s and 70’s fastback mufflers, and the sound you get from using this exhaust reflects that. The entire system features full stainless steel construction throughout including these straight through design Magnapack mufflers, the 2.5” mandrel bent tubing, all exiting out these 3.5” brightly polished tips. Because Ford chose to weld the factory exhaust on these cars, you will need to cut it off before getting started with the install. Once you have it out of the way, getting the new Magnaflow system installed should only take you about 2 hours from start to finish. Now let’s hear how Magnaflow’s Magnapack sounds compared to our factory exhaust.
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Features, Description, Reviews, Q&A, Specs & Installation
Note: Coupon codes cannot be applied to this product.
Fitment: 1999 2000 2001 2002 2003 2004 Details
CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
September 02, 2019
Magnaflow competition cat back
Love the sound, hate the quality, passenger side great fit, driver side Up and over axle little clearance slight bumps and pipes hit sway bar. Twice now I’ve had to adjust and tightened the band clamps for the price you pay that shouldn’t beHelpful (0)
December 10, 2018
Just woke up my 1999
Tight tolerances, awesome performance and sound increaseHelpful (4)
November 23, 2018
I have this in Cali
To start off, I absolutely love this setup. Its loud enough to set off car alarms but not too loud as to wear your constantly waking up your neighbors if you start your car up lmao. I live in San Diego and have this set up attached to the stock 6 cats on my 99 GT and it will pass emissions tests with flying colors. So if your in Cali and want an AWESOME sound for your GT and want to stay legal, then this is the way to go.Helpful (6)
August 16, 2018
Best exhaust hands down
Like the title says, it’s the best exhaust system for your 99-04! A very deep and not obnoxiously loud exhaust by itself. But if you pair it with a BBK O/R x-pipe like I did, watch out! It sounds like a monster unleashed! Very deep and actually not too loud at highway speeds, can have a convo. Would highly recommend!Helpful (7)
April 29, 2018
Sounds so sweet! Very good design and great product.Helpful (8)
April 02, 2018
Omg The difference. I went from a completely stock set up to this catback. No headers, stock H pipe with cats and the sound was still amazing. Highly recommend this. At idle the sound is low enough not to annoy neighbors but once you get on it... wow that rumble.Helpful (7)
November 25, 2017
nice unit its loud magna flow allmstainlees steel had all connections weildedHelpful (8)
November 23, 2017
Had stock exhaust on my wife's 2001 GT, MAN this cat back exhaust sounds GREAT! Not sure about any increase in HP, but the amazing sound makes it feel like it, LOLHelpful (8)
November 19, 2017
Very happy with this exhaust!
You should add $50 to the price and throw in some hangars and stainless flange studs.Helpful (8)
August 24, 2017
Perfect sound for the Mustang! Even in the convertible, it's throaty, but not too loud! Aggressive and smooth!Helpful (8)
will mac pro chamber work with this i am in the market for an exhaust i am thinking about getting mac long tubes w/ pro chamber and not exactly sure about cat back byt like the sound of the magna pack my question is will all these components work together
Yes the prochamber will work with the magnapacks, this is the setup i currently have on my 2000 gt and it sounds amazing
Will this fit a v6 with v6 x-pipe
No, this Catback was designed to only fit V8 model Mustangs.
Is this legal in ct
We recommend reaching out to your local DMV or state inspection location for your states laws regarding exhaust regulations.
would this fit with after market xpipes on a 2004 gt
this would fit on your mustang.
to install this in a 04 Mach 1 would I need anything else like x pipes or would this be the only thing I need to buy for the entire system?
Nothing else would be needed for the install no.
This kit does come with Mufflers, but as a Cat-back does not include cats.
Yes, the Magnaflow Competition Cat-Back Exhaust uses Magnaflow's Magnapack mufflers in this system.
Unfortunately this Magnaflow Competition Cat-Back Exhaust is not tested or approved by the California Air Resource Board meaning it is not legal for use upon public roads in California.
If the headers and mid pipe used in the 5.0 swap met at the same position as the stock 99-04 mid pipe then yes this catback would work.
The Magnaflow Competition Cat-Back Exhaust - 2.5in. (99-04 GT, Mach 1, Bullitt) will fit both manual and automatic mustangs.
This Magnaflow Cat-Back and Pypes Catted X-Pipe will definitely work together. This Cat-Back combined with an X-Pipe will be extremely loud and raspy. An X-Pipe tends to have more of an aggressive, raspy tone to it. If you are looking for something a little more toned down, I suggest going with an H-pipe. This will give the car more of a muscle car sound. I suggest going on YouTube and listening to some exhaust clips to give you a better idea of what everything sounds like.
Get in touch with your most reliable muffler shop before making any mods to a CA car. They can tell you what will pass and what won't. I made the mistake of buying a GT that didn't have all four cats. Couldn't pass emissions tests without investing about a grand to bring it back to almost stock configuration. However, I do have a friend who installs his stock set-up to pass smog, then when it passes he replaces it with his beasty exhaust system until it has to be smogged again.
To make this Magnaflow Competition Cat-Back Exhaust - 2.5in. (99-04 GT, Mach 1, Bullitt) work with your V6 you will need to purchase the PaceSetter V6 Dual Exhaust Adapter Kit (99-04 V6) Item #51063 (http://www.americanmuscle.com/pacesetter-adapter-kit-9904v6.html)
Hi, The PaceSetter V6 Dual Exhaust Adapter Kit Item #51063 will work with Magnaflow Competition Cat-Back Exhaust - 2.5in or any 99-04 GT Cat-Back.
MagnaPack over the Loudmouth for deep resonant tone. Loudmouth tends toward raspy more like a foreign exotic. Another option is Flowmaster Super 44's. Beautiful exterior tone with minimal cabin intrusion. I run those on one of my GT's and the other has MagnaFlows which have a different tone that is just as nice but I run larger exhaust tubing on that car so it's much louder. I'm planning to switch those out for Super 44's soon because I like their tone better. Just sayin'.
(approx) 2 Hours
Light to Moderate mechanical skill required.
What's in the Box
|Piping Material:||Stainless Steel||Tip Material :||Polished Stainless Steel|
|Piping Size:||2.5"||Tip Size:||3.5"|
|Muffler Type:||Straight-through||Fitment:||1999-2004 GT, Mach 1, Bullitt|