Placement of mufflers for best sound on a crew cab?

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OldBlueDually

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Gents, I will be continuing on the exhaust work on my 76 crew cab. I would like to know where my mufflers should go to get a good deep grumble from the exhaust system.

Searching this forum, and others has not really given a clear answer, and maybe there isn't one??....

The mufflers I have are smitty, around 30 inch length. The exhaust tubing itself is 3". The exhaust will exit in front of the rear tires. The engine is a 455 Olds (which in itself has a heck of a deep tone).

As of now, I have the mufflers placed under the cab (mostly under rear passengers side of the cab), with the exhaust turned out in front of tires. I left the exhaust together as it was when I took it out from the truck (used to exit it behind rear tires, will not exit in front).

Any suggestions to have a great deep sound out of this truck? Thanks in advance!


Here is what the exhaust pieces look like (I don't have pics under the cab...yet);

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Here is the exit location of the exhaust;

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Catbox

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On my truck, we have the mufflers right in front of the rear axles.
They each dump with an angled piece of tube right after the muffler.

This is basically how it is now, we just took the Flowmaster Delta 40 2 chambers out from under there as they were too quiet. They were replaced with a set of Jones Flow Pack single chamber mufflers, which are surprisingly quiet as well behind a big block with headers on it.

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DoubleDingo

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Pretty sure how you have them, it will rumble just fine
 

Dave M

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On my truck, we have the mufflers right in front of the rear axles.
They each dump with an angled piece of tube right after the muffler.

This is basically how it is now, we just took the Flowmaster Delta 40 2 chambers out from under there as they were too quiet. They were replaced with a set of Jones Flow Pack single chamber mufflers, which are surprisingly quiet as well behind a big block with headers on it.



That's how mine were, I got tail pipes added to exit out the back. I found it would drone and resonate under the tub too much.
 

OldBlueDually

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Gents, thanks for the input! I will leave them in that spot then for now ;)

I hope today to do some work on it!!
 

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