Muffler palcement opinions

[GrabberGT]

Im looking for experienced opinions on muffler placement. Id like to know if there is a reduced interior cabin sound if mufflers are placed behind the axle rather than in the stock locations under the rear seats. I like the way my car sounds but its terrible when cruising. I like it being loud but would like to hear the stereo (and my own thought) when cruising down the highway. Im running Flowmaster Super 40's with turn downs just before the bumper. I know what I was getting into when I bought them but thought that with enough interior insulation I could tame them. I considering going with a bullet style mufflers placed on either side of the fuel tank like this:

[Tony_SS]

I think I would just replace the flowmasters with magnaflows or something instead of trying to work around them...just my 02

[jy211]

I saw the show where they built this car. They have 4 mufflers on it I believe to quiet it down.

http://www.ridetech.com/garage/2011/...1964-cadillac/

I want my '55 nice and quiet to, but once I mash on it, I want it to roar

[Sieg]

How much interior insulation do you have?

FWIW - I used Dynamat Extreme and 1/2" wool fiber carpet cushion to line the rear upper and lower seat backs and the car is pretty quiet inside. Using the original transverse mounted dual in/out Flowmaster w/ stock tip locations.

[GrabberGT]

Originally Posted by Sieg

How much interior insulation do you have?

FWIW - I used Dynamat Extreme and 1/2" wool fiber carpet cushion to line the rear upper and lower seat backs and the car is pretty quiet inside. Using the original transverse mounted dual in/out Flowmaster w/ stock tip locations.

I have 2 layers of Fatmat, 1/2" Jute, then molded carpet. The trunk is completely sealed off with rear bulkhead insulated the same way. Side panes also sealed off with Fatmat. There is no Fatmat in the trunk. Just foam backed carpet.

Something else that may make a difference. I have no X-pipe or H-pipe. I've been told this will help to mellow out the sound some.

[Tony_SS]

An X-pipe will make a huge difference.. I know mine did. I have an X-pipe and Magnaflows and am really happy with how it sounds... no drone, no rasp or blumpy idle... just clean, smooth sound until you open it up.

[Sieg]

How thick is the seat material? It might be worth adding material there and see what happens. It take less than an hour. You might be able to get scraps dense 40 oz. fiber cushion from a local flooring retailer. It's much denser than the factory carpet pad.

I have a H pipe but it was installed with the system so no comparison. Seat of the pants says an X pipe would be beneficial.

[andrew69_04]

The x-pipe will really help with the sound. Im not sure if the placement of the mufflers is going to fix your interior drone your getting. you may have to swap to a different brand of muffler