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Flowmaster FlowFX?

UPS says the muffler should be here on Monday. Interesting that Stage 3 is in Arizona and Magnaflow is in West Sacramento, CA, yet the part shipped from Kentucky. Somebody apparently has a warehouse in KY...
Sounds like you got an awesome deal! Congrats
It's a 402A w/5.0L and about $6k in other options. Lots of stuff I probably would have skipped had I ordered it myself.
 
UPS says the muffler should be here on Monday. Interesting that Stage 3 is in Arizona and Magnaflow is in West Sacramento, CA, yet the part shipped from Kentucky. Somebody apparently has a warehouse in KY...

It's a 402A w/5.0L and about $6k in other options. Lots of stuff I probably would have skipped had I ordered it myself.
Magnaflow owns Flowmaster?
 
Muffler came today at about 1 PM. Went to car wash to hose all the crud out from under the truck. Got my floor jack from the other shop and raised up the passenger side and put a jack stand under the frame rail and then sprayed all of the bolts and connections with PB Blaster. Let it sit for a couple of hours to dry out and let the penetrating oil do its thing. Took less than an hour to pull the old system off. I stopped at 4:30 to eat dinner and then I'll put the new system on. If nothing else it should be about 20 lbs lighter than the factory muffler.
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Muffler came today at about 1 PM. Went to car wash to hose all the crud out from under the truck. Got my floor jack from the other shop and raised up the passenger side and put a jack stand under the frame rail and then sprayed all of the bolts and connections with PB Blaster. Let it sit for a couple of hours to dry out and let the penetrating oil do its thing. Took less than an hour to pull the old system off. I stopped at 4:30 to eat dinner and then I'll put the new system on. If nothing else it should be about 20 lbs lighter than the factory muffler.View attachment 35186View attachment 35188View attachment 35189View attachment 35190View attachment 35191
Awesome, looking forward to the new rumble!!!
 
Here 'tis. Maybe I can try to get something better tomorrow. If the roads are clear I'll try to get some in-car video so you can listen for drone, etc.

 
Here 'tis. Maybe I can try to get something better tomorrow. If the roads are clear I'll try to get some in-car video so you can listen for drone, etc.

Nice, sounds a bit quieter than I expected.
 
Nice, sounds a bit quieter than I expected.
And that's exactly what I was going for. On my last 5.0L truck I went with a Mangaflow system that was similar to this, single 3" in, dual 2.5" out except both tailpipes exited in front of the rear tire on the passenger side and it deleted the factory resonator. It looked really cool but it probably exited too far forward. Way too load and too much drone. To make it at least livable I had to add a resonator back in. That's why this time I decided I wasn't going to remove the resonator at all so when I saw this Flowmaster muffler I thought... that's the ticket. It's relatively inexpensive and it does exactly what I wanted.
 
How is the volume vs stock? Cold start, normal driving, and when you get on it?

And how is the sound compared to stock?

Overall, any complaints?

[sorry for playing 20 questions]
 
Okay okay, you can stop twisting my arm.
I’ll take that Grabber Blue Fastback off your hands. 😎
With that being said and although I’m a Borla man, that new FLOWMASTER muffler with the stock resonator does sound very nice. Fingers crossed that you don’t get much if any interior drone.
 
How is the volume vs stock? Cold start, normal driving, and when you get on it?

And how is the sound compared to stock?

Overall, any complaints?

[sorry for playing 20 questions]
I added this to my truck last weekend, but on a 3.5L ecoboost. To my hear, it's marginally louder when starting and accelerating but with a more guttural, throaty sound which i like. Zero drone on mine i'm sure due to still having the resonator. Zero regrets or complaints for me. And i agree with blksn8k that the factor muffler is heavy!
 
Okay okay, you can stop twisting my arm.
I’ll take that Grabber Blue Fastback off your hands. 😎
With that being said and although I’m a Borla man, that new FLOWMASTER muffler with the stock resonator does sound very nice. Fingers crossed that you don’t get much if any interior drone.
That's a respectful NO on the Mach 1. It's a '70 428CJ, 4-speed car and when I got it it was an empty, rusty shell. The only thing I didn't do myself was paint it. Well, I did repaint the hood and roof myself within the last year but the rest of the paint is now about 11 years old.
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One difference that I was pleasantly surprised by on this truck vs my previous 2018 is that on the old truck with the stock system everything from the Y pipe flange to the muffler was only 2-1/2". On the Tremor that is all 3" which was another reason to leave it alone. On the other truck I ended up adding a 3" Magnaflow resonator but there was no good reason to do that this time.
 
I've tried to upload a 20 second video of how the Flowmaster FX sounds on the EcoBoost but apparently the file to too large. If anyone would like to hear it, feel free to message me.
 
I've tried to upload a 20 second video of how the Flowmaster FX sounds on the EcoBoost but apparently the file to too large. If anyone would like to hear it, feel free to message me.
For all of my videos I just upload them to my YouTube channel and then post a link to them to wherever.
 
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Speaking of videos I had to make a grocery run today and made a couple of videos along the way. I'm hesitant to post any of them however since you can see both my speedometer and the speed limit signs along the highway. :oops:

The only time I could hear any real droning sounds was on acceleration and while climbing a grade. At normal cruising speed in top gear it is no louder nor any more annoying than the stock system. As a matter of fact, at cruising speeds the General Grabber X3s make more noise than the exhaust does.

Does anyone know what the purpose is of that rubber damper looking thing in front of the stock muffler? I'm tempted to cut it off and clamp it to the inlet side of the Flowmaster muffler...
 
OK, so I was bored. Probably just my imagination but it does seem to be a little quieter with this thing on there.


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That's a respectful NO on the Mach 1. It's a '70 428CJ, 4-speed car and when I got it it was an empty, rusty shell. The only thing I didn't do myself was paint it. Well, I did repaint the hood and roof myself within the last year but the rest of the paint is now about 11 years old.
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Sweeeeet. 😎
 
That damper is to cut down exhaust NVH.
 
That damper is to cut down exhaust NVH.
After I took that photo I realized that on the original muffler the damper was mounted in the opposite direction. I doubt it matters functionally but if I decide to permanently weld it in place I will flip it around so the metal bracket is on the front. My guess is they did it that way originally to protect the rubber from road debris.
 
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