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4 mufflers exhaust on 3" pipes

john.thompson068

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I have a 540 hp 440 with 1 7/8" headers, 3" collector, H pipe, 3" Flowmaster 50 series and tailpipes. It is very loud; too loud. I want to be about as loud as a stock type muscle car would be, but not whisper quite like a Corvette.

I do not believe that the 70 series Big Block II Flowmaster mufflers will be very much quieter. I already went from reusing my old 2 1/2" 40 series with turn downs to the correct 3" 50 series with tailpipes and while it was a tiny bit quieter, I believe the 70 series will again only be a tiny bit quieter, and I need a lot quieter. I also do not believe that any single pair of 3" mufflers would actually be quite on a motor like this with big exhaust. I watched a youtube video with a guy using 70 series Flowmasters on a 540 big block and even without speakers on my computer, I could tell it would still sound just as loud.

So my solution is to install a pair of Dynomax 17267 Ultra-Flow SS mufflers in front of the Flowmaster 50 series.

Being the Dynomax are a straight through 3" center in center out design muffler, adding this second pair of mufflers will not restrict exhaust flow or reduce performance.

The Silver Bullet had four mufflers. I too have a 66 Satellite. What do you think about all of this?
 
I will probably be going down the same road as you because I want my 69 RR reasonably quiet. My thought was to add a resonator in the tail pipe. I have done this on a car I built for a buddy and it worked very well. The car wasn't anything hot - 62 Merc with single exhaust - but he didn't like the turbo muff I put on it so the solution was to add a glass pack as a resonator. HUGE sound reduction and it didn't seem to hurt performance, probably because the resonator was added at the very end where the exhaust gas was cool thus not creating a big restriction. The next thing is to see if I will have room for a straight through cylindrical silencer with the TTI 3" tailpipes. May end up making a set.
 
I will probably be going down the same road as you because I want my 69 RR reasonably quiet. My thought was to add a resonator in the tail pipe. I have done this on a car I built for a buddy and it worked very well. The car wasn't anything hot - 62 Merc with single exhaust - but he didn't like the turbo muff I put on it so the solution was to add a glass pack as a resonator. HUGE sound reduction and it didn't seem to hurt performance, probably because the resonator was added at the very end where the exhaust gas was cool thus not creating a big restriction. The next thing is to see if I will have room for a straight through cylindrical silencer with the TTI 3" tailpipes. May end up making a set.

What do you mean by adding the glass pack as a resonator? I am not sure what a resonator is. Also, if the glass pack was a straight through design and the same diameter as the rest of the pipes, why would it matter if it is at the end of the exhaust where the gases are cool? That is good though that it made a HUGE reduction in sound.
 
I just replaced some Flowmaster 50s with Dynomax Ultraflows and the car quieted down some. Made it a bit deeper toned too. I like them better plus they are much less restrictive.
 
What do you mean by adding the glass pack as a resonator? I am not sure what a resonator is. Also, if the glass pack was a straight through design and the same diameter as the rest of the pipes, why would it matter if it is at the end of the exhaust where the gases are cool? That is good though that it made a HUGE reduction in sound.


A resonator is like a small muffler at the end of the system. Some factory Hi perf MoPars had them. The effective diameter inside the glass pack or resonator is smaller than the pipe especially when you factor in the boundary layer due to turbulence. And being the exhaust gas has cooled and condensed by the time it sees the resonator it doesn't require such a large diameter pipe to get good flow. Might be able to get away with a 2.5" ID resonator if there is such a thing. Some modern cars have them too so maybe steal from there.

Here you can see what it is.
http://www.accurateltd.com/1968-70-...te-Exhaust-System-for-Exhaust-Tips_p_209.html
 
A resonator is like a small muffler at the end of the system. Some factory Hi perf MoPars had them. The effective diameter inside the glass pack or resonator is smaller than the pipe especially when you factor in the boundary layer due to turbulence. And being the exhaust gas has cooled and condensed by the time it sees the resonator it doesn't require such a large diameter pipe to get good flow. Might be able to get away with a 2.5" ID resonator if there is such a thing. Some modern cars have them too so maybe steal from there.

Here you can see what it is.
http://www.accurateltd.com/1968-70-...te-Exhaust-System-for-Exhaust-Tips_p_209.html

Okay. Thanks for the information.
 
Dynomax turbo's pretty throaty. I found, on my old 340 swinger, that Walker made a hemi muffler; they were perfect.
 
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