Exhaust muffler data

[aquaman0001]

Hello,
I have looked and read dozens of threads looking for an answer on interior noise for a 4" exhaust. "Everyone" has an idea of what loud or quiet is, but what I am looking for is data comparing the larger exhaust or muffler noise compared to stock?
http://www.flopro.com/FP2500oval.htm has a chart for there mufflers compared to stock. Does anyone know of any other manufactures that has this type of comparison for there system?
Thanks
A

[Robyn]

Well I dont have any hard and fast Data that speels it out in DB A but my good old ear dyno can tell you that the Banks Stinger system on the dually is sweet.
The interior is very comfortable even with the windows down some. The Cd player does not have to be turned up to the moon to be heard..
The biggest iisue I have with so many of the exhaust systems is that many of them will hit a harmonic that resonates something aweful in the cab.

I have not ridden in any with a 4" system though on a 6.5. Mine is a 3-1/2 and seems to be plenty for the 6.5 to breathe through.

The tone is mellow and far off with no pop or rapping, just a low mellow note that pretty much stays the same all the way up the power scale.

Not sure where you could find actual data on the DB level of any particular system.
I would say that my trucks interior noise level with the windows up is somewhere in the 70 Db or so, maybe a tad more.
But as I said the stereo does not have to be cranked to enjoy it.

You can also get a lot of noise from the air intake too depending on the system.

The dually had the air box all hacked up and had a K-N filter in it.
Tossed the whole lot of it and put a good air box back on with a good all paper filter.
The K-N was letting more crap though than I am going to sit still for as I live in on 4 miles of dirt road.

Hope this gives you something positive

Robyn

[DennisG01]

Unfortunately, I don't think you're going to find what you're looking for. I can't say I've ever specifically looked for that, but I definitely don't recall coming across that info anywhere. Most of the "open" muffler systems give you the option of being able to turn the muffler around. One way is a little throatier.