Magnaflow Exhaust For The 2015 Mustang Gt

84Ttop

They make new pistons every day, so why worry?
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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.
This kit is a cat back kit and retains the factory catylitic converters. This mod requires no tuning whatsoever. If you were to remove the cats which I recommend against, then tuning would be required and even them passing emissions standards would be extremely difficult if not impossible.
 
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Dirty Rod

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Thanks. I thought that it was replaced by that X-pipe section. Appreciate the info.
 
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jastang

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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).

Sorry, but I just don't see the gains you're talking about across the power band. All the gains seem to be above 6k and torque now drops off a little sooner. The first pull was started about 1,000rpm sooner (at 2k) than the second. This may have to do with what the computer calculated as average gain. I love Magnaflow and hope to put a similar kit on my '15, when I finally get it in the garage.
 

Noobz347

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Sorry, but I just don't see the gains you're talking about across the power band. All the gains seem to be above 6k and torque now drops off a little sooner. The first pull was started about 1,000rpm sooner (at 2k) than the second. This may have to do with what the computer calculated as average gain. I love Magnaflow and hope to put a similar kit on my '15, when I finally get it in the garage.

upload_2015-3-4_12-26-32.png
 

jastang

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Yes, I can see that the computer calculated that number. But I don't think that number is accurate. How do you get an average gain of 20hp when there was never even a peak gain of 20hp? That makes no sense. The second pull went to about 6800rpm and made its peak hp there. The baseline was cut off a little sooner. That may average out across the pull to 20 hp, since it was making about 350hp while the baseline had already coasted down to the 200hp range. It's apples and oranges. You have to look at the data points themselves, not some number the software spat out.
 

jastang

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After thinking about it (don't I have anything better to do?!) it's not the difference in the few hundred rpm higher the second pull went, but the fact that the second pull didn't start collecting data until 3k rpm as opposed to 2k rpm. If you start collecting data when the motor is spinning faster and making more power, of course the average is going to be higher. The lower numbers from 2k-3k are not factored in. If you plugged in zeros for the second pull where there is no data, the average would drop drastically. More realistically, if you plug in the baseline numbers from this range for the "improved" pull, you get more of an "apples to apples" comparison. The best numbers to compare fairly would be the Baseline numbers omitting 2000-2500rpm. That or you could plug in the baseline hp and torque for the improved pull for that same range. In short, it was not a good measurement for calculating average power numbers. Parameters should be have been kept much closer to each other. (read: should have started second pull at 2k rpm). Starting at 3k not only left out the numbers from 2k-3k but the motor simply wasn't making as much power yet at 3k, as the throttle had just been mashed. Conclusion: Bad dyno test.
Screen Shot 2015-03-05 at 12.39.01 PM.png
 

84Ttop

They make new pistons every day, so why worry?
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Not sure I see where you get the bad dyno test information from? Peak numbers improved and the engine was spun past peak power and torque on both occasions.. Showing where the peak is in both rpm and hp are the biggest basis for my results.
 

justinakajuice

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Not sure I see where you get the bad dyno test information from? Peak numbers improved and the engine was spun past peak power and torque on both occasions.. Showing where the peak is in both rpm and hp are the biggest basis for my results.
Either way 84, your current numbers are much more happy banana icon.
 
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