Magnaflow Exhaust For The 2015 Mustang Gt

84Ttop

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With the release of the new 2015 Mustang comes a long list of aftermarket parts to compliment these cars. Magnaflow has stepped up to the plate in a big way and is offering the best exhaust components for these cars. This is not unexpected as Magnaflow has a long history in building top quality stainless steel exhaust systems that not only make big performance gains that sound great but are backed with a life time warranty!

We recently got our hands on the Competition cat back kit for our 2015 Mustang GT and will detail the installation here. You will find our before and after dyno testing along with pictures of the installation and a step by step guide to help you do this work simply and easily whether it be in your home garage or driveway. Dyno videos and sound clips can be found towards the bottom of this post as well.

Lets start with the test subject:

2015 Mustang GT Automatic
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For base line testing we strapped the car down to the rollers with only 65 miles on the odometer. This car hasn't even seen a full tank of fuel through the injectors yet!
Our initial dyno testing proved that the Coyote engine is as stout as they say it is and laid down 372 RWHP and 347 ft/lb RWTQ through the automatic transmission. For the testing we are using All Out Automotives in house Dynocom Chassis Dyno.

Here are the initial results:
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Now it's time to get down to business and get the car up on the lift for the install!
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The factory exhaust has a huge resonator in the center of the car and big bulky mufflers. The car is very quiet from the factory and surly is missing that Magnaflow exhaust tone that every mustang owner has become so familiar with.

Here you can see the factory cat back system:
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To remove the factory exhaust you need very few tools. There are 6 bolts holding 4 exhaust hangers in place and a ratchet with a short extension and an 13mm socket remove these easily. I will say that Ford engineered the hangers right, they have clips that hold the exhaust loosely in place even after the bolts have been removed. To disconnect the catback from the rest of the car you will need a 15mm socket and only need to loosen 4 bolts on the factory clamps to do so. With the help of a friend the factory exhaust is easily lifted down in one piece

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Now on to the good stuff. We layed the Magnaflow exhaust out to compare to the factory catback

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Mandrel bent 3" stainless exhaust never looked so good. The quality is easy to see when you deal with Magnaflow. Perfectly mandrel bent tubing and beautiful factory welding. The polished mufflers and tips have a mirror finish that you can comb your hair to.

For the install we first loosely connected the new X pipe to the remaining factory exhaust re using the factory clamps. 4 15mm bolts hold this into place. Be sure to only snug these connections, the complete exhaust must be in place before tightening any connection completely.

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Next we installed the intermediate exhaust piping and reinstalled two of the factory hangers. Magnaflow uses factory style band clamps that even have the same size nuts and bolts to make this install flawless!
13mm bolts hold the factory hangers in place as these are reused for your new exhaust system. 15mm bolts can be found on the clamps that will hold the intermediate tubing to the X pipe. Again, leave these connections loose until all of the exhaust system is installed.

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Now we get to the mufflers! Polished stainless steel works of art if you ask me. These things have a polished finish that is just brilliant! Reinstalling the final two factory hangers each one taking two 13mm bolts allows you to install the mufflers. Each muffler will require the use of the included factory style band clamp. These band clamps are again 15mm and really make this whole job a 2 tool project. Take a look at the mufflers installed.

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Now that you have everything mocked up into place you can carefully tighten all of your exhaust connections. This kit fit so perfectly that there was no adjusting to do! We simply started tighten the clamps in the front and worked our way back. This is the time to look at the 4.5" exhaust tips to see that they are centered in the exhaust cut outs and your on the home stretch.

Here are a few photos of the completed exhaust system:

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The tips fit perfectly!

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The install time was less than 30 minutes and the guys at All Out Automotive made quick work of it. This system was designed with the end user in mind and can easily be installed by even the most novice car enthusiast. Please keep in mind that if you are doing this project at home you MUST use jack stands and always ask for a hand. Safety is key here, an ounce of prevention goes a long way!

At this time we fired the car up to hear that beautiful tone that only Magnaflow can provide!


View: http://youtu.be/Zq2NQmDS_Lc


Above you will find our start up clip combined with a sound bit from the car running on the dyno.

Now it is time to strap the car back down to the rollers and see the gains we are rewarded with!
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Increases in hp were apparent from the very first pull, we made a total of 6 dyno pulls to verify our results and they were all very consistent.
RWHP increased by 10 and RWTQ increased by 5.5 ft/lb's !!!
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These gains are substantial and nothing to sneeze at! By simply replacing the cat back system on our 2015 we increase the rwhp by 10! This involved 2 tools and less than one hour of our time. Not only do you feel this in the seat of your pants but you can hear the difference too! If you thought the 2015 Mustang turned some heads already, just wait until you have your Magnaflow exhaust system installed! While I'm impressed with the results from our automatic equipped car, stick shift equipped cars should see even larger gains!

Overall we have learned a few things about the 2015 Mustang and Magnaflow. The new Mustang platform is potent and that's hard to argue. Adding Magnaflow exhaust has not only been easy to do but has rewarded us with more HP and a more aggressive sound. This Magnaflow system uses top quality products and will stand the test of time all while adding that iconic sound that only Magnaflow has! The fit and finish of their products is spot on perfect!

Check out Magnaflow's website here: http://www.magnaflow.com/

Follow this link to see the exact Magnaflow product that we used for this testing and installation:
http://www.magnaflow.com/02product/shopexd.asp?zone=all&id=5398
Now that you have seen the great styling, heard the incredible sound and witnessed the awesome performance gains that Magnaflow can provide for you Mustang it's time to contact one of our site sponsors for the best pricing on YOUR new Magnaflow exhaust!

Now that the snow has cleared and I am afforded some better weather I just wanted to show off just how well that exhaust fits and how incredible it looks.
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FoxMustangLvr

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So when is the first 1/4 mile run? Dyno is a good indicator for HP progress but I thought you'd do a bone stock shake down first before modd'ing the beast!!!!???
 

mikestang63

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Nice!!! 20 rwhp and the motor hasn't even been broken in yet. Plus I get that dropped a good 10-20 lbs off the car. Let's see some track times!
 

TOOLOW91

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Nick not only am I shocked at how much the car picked up through the whole entire pull but - The fit and finish is just perfect . Nothing makes it better then when tbe tips are perfectly shaped and placed in a bumper . Sounds mint as well . Looking foward to more progress . Great review !
 
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84Ttop

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The weather around here (Northeast) hasn't been too great for hitting the track. The car will likely have many mods before it actually hits the 1320.

Thanks for the compliments on the exhaust too guys. The credit is surely due to Magnaflow! Can't say enough about how well their product works!
 

TOOLOW91

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The weather around here (Northeast) hasn't been too great for hitting the track. The car will likely have many mods before it actually hits the 1320.

Thanks for the compliments on the exhaust too guys. The credit is surely due to Magnaflow! Can't say enough about how well their product works!
These cars are impressive for sure exhaust only I am sure wouldn't disappoint in the 1320
 

FoxMustangLvr

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You're going to wish you had a stock base time for the 1320, I hope you don't get too crazy till you do! But that just me talking.....:shrug:
 
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84Ttop

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These cars are impressive for sure exhaust only I am sure wouldn't disappoint in the 1320
Agreed, with more tq and hp at the tires you better believe that ets will improve at the street as well as increase your "driving experience" at the track
 

srtthis

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I must say the fit and finish on this seems to be top notch! How do the graphs over lay? Any big gains in the mid range?
What's your overall thoughts on the new car?
 
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FoxMustangLvr

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Nice!!! 20 rwhp and the motor hasn't even been broken in yet. Plus I get that dropped a good 10-20 lbs off the car. Let's see some track times!

Where do you and Noobz get 20 rwhp from? Stock dyno run was 372 and after the exhaust install it went to 382, that's 10 rwhp! Stop drinking and posting :drink: Still a good gain though :nice:
 

Noobz347

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Where do you and Noobz get 20 rwhp from? Stock dyno run was 372 and after the exhaust install it went to 382, that's 10 rwhp! Stop drinking and posting :drink: Still a good gain though :nice:


Average power = 257.6 Dyno 1. It's the average over the entire pull.
Average power = 296.3 Dyno 2. So I was off. It's nearly 30 HP. lol

That's right about SOTP territory there.
 

mikestang63

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Where do you and Noobz get 20 rwhp from? Stock dyno run was 372 and after the exhaust install it went to 382, that's 10 rwhp! Stop drinking and posting :drink: Still a good gain though :nice:

look at the bottom of the dyno charts- before and after... as Noobz said it's actually a 30hp avg gain.
 
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FoxMustangLvr

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So if you guys put your car on the dyno, what number would you report to us Stangnet'ers? The avg HP or your best peak HP number? :scratch: Even Nick reported 10 rwhp. Maybe I don't know what I'm talking about, I'm no dyno guru.
 

TOOLOW91

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So if you guys put your car on the dyno, what number would you report to us Stangnet'ers? The avg HP or your best peak HP number? :scratch: Even Nick reported 10 rwhp. Maybe I don't know what I'm talking about, I'm no dyno guru.
the peak is 10hp - but the avg horse power went up almost 30 across the whole graph . The peak is what we are most interested in but 30 hp avg diff is a big number
 

Noobz347

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So if you guys put your car on the dyno, what number would you report to us Stangnet'ers? The avg HP or your best peak HP number? :scratch: Even Nick reported 10 rwhp. Maybe I don't know what I'm talking about, I'm no dyno guru.


Doesn't really matter what you report. Peak numbers are great for comparing to a baseline. It's an immediate indication of improvement.

Average HP gain over the usable range tells you how much better it will perform. At the track and even more on the street.

It means that on average, across the entire run, there was a 30 HP increase. Not just the 10 HP difference at the very top of the usable range (who really runs up here that's not on a race track).
 

84Ttop

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Doesn't really matter what you report. Peak numbers are great for comparing to a baseline. It's an immediate indication of improvement.

Average HP gain over the usable range tells you how much better it will perform. At the track and even more on the street.

It means that on average, across the entire run, there was a 30 HP increase. Not just the 10 HP difference at the very top of the usable range (who really runs up here that's not on a race track).
This response is spot on! Most people are interested in peak HP numbers and that is the reason for reporting them. I also provided the pre and post graphs so that they can be analyzed. The average hp gain is more than impressive and why the seat of the pants feel is there after bolting up the new system.
 
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MikeH686

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Why am I so late to this!! The car looks awesome the fit looks stock, the gains are awesome and the sound is good too! Good job all out auto and @84Ttop
 
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Dirty Rod

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Dumb question but, since the only cars I've modded didn't have a cat, I'll ask it.

I assume the computer will sense the cat is missing so is there a mod to prevent the check engine light from coming on or to pass smog? Back in the day it was a pain to reinstall stuff to pass so I'm assuming there is an easier work around these days.

I did GTS and folks were talking about a sensor mod but I didn't see it in the write up.