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Old 05-31-2018, 11:43 AM
RustyNCa RustyNCa is offline
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Originally Posted by sidewalkman View Post
I couldn't agree less...I installed 2.25 staggered Flowmasters out back, and there is no drone at all, sounds just hotrod enough but not loud. Mind you I did the whole floor in dynamat when I replaced the carpet so that didn't hurt. But I like the sound of flowmasters!
Well, I'd say you had better luck than I. I like the sound of the flow masters on my Olds, but they drone so bad it will clear your sinus at 2k rpm. My 3rd gen Camaro had a single flowmaster made the poor thing sound like a V6, so we redid the system with glasspacs sounded 100% better. On my CTS-V, we cut the flowmasters off and I now run no mufflers, less drone, oddly, no louder but now has a pop every now and again when you shift.

Have one on my suburban which also drones not as bad as the old, bigger cabin? But since she has become the old beater I just live with it.

We tried them on my 58 TBird, but didn't like them way out back.

I've just not had good luck with them.....
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Old 06-01-2018, 04:23 AM
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simplyconnected simplyconnected is offline
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Originally Posted by StealthSRT10 View Post
It really depends on a few factors.

1. which flowmaster muffler you get (ex. 40 series, or 50, or 10) lower the number the louder it is.

2. if they are Delta flow. supposed to cut down on drone.

3. where they are dumped. (under the car or out the back
Add this to your list:
  • Diameter of the pipes in your system,
  • The cam your engine is running,
  • The CI of your engine,
  • The compression ratio. <--Very high compression sounds like a shotgun every time a cylinder fires.
  • Number of chambers in your #1 and if resonators or catalytic converters are installed.

I put 3-chamber Flowmasters on my stock Mustang GT thinking, when I retrofit from the 5.0 to the 351W, the 3-chambers would still be quiet enough. WRONG. My neighbors' windows rattled, the radio/CD was useless, etc. It was a treat to put the top down just so I could think. The car was a rocket and too dangerous to let my kids borrow it. Eventually, I wore holes through the back ends of both Flowmasters.
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Old 06-01-2018, 02:23 PM
Deanj Deanj is offline
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Once I installed Borla mufflers on my L48 1980 Corvette 4 speed.

Before the installation, I installed an Erson cam 208/208 which had more lift and duration than the L48 cam, and a free flow cat that you actually saw light through. The result was disastrous with drone, loud cabin noise, and vibration.

I went back to stock mufflers and these provided great sound because of all the engine and cat changes.

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Old 06-01-2018, 05:54 PM
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sidewalkman sidewalkman is offline
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My Mufflers are MAGNAFLOW 13235 XL Performance Muffler Oval 4x9x14 Offset/Offset 2.25/2.25, on a stock 352. Like I said, no drone, a friend of mine has Dynaflows on his Duster (Stock 340) and the drone loosens your fillings at 1800-2500 RPM, but mine is good. But like I said, the Dynamat likely is more the solution than the mufflers!
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