So I am currently running a (pretty sure) 4"x9"x18" muffler. I am/was comfortable with it when I wasn't running dumps. It was quiet when it needed to be, but was throaty when I jumped on it.

Here is my question...would going to a shorter length greatly effect the noise level of the muffler? I know the general statement, a shorter muffler is louder...blah blah, but I mean will 4" will make that big of a difference?

Also, when it comes to the oval bodies, what would constitute purchasing a 5x8 as compared to a 4x9? (other than fitment issues)

Just trying to see what all you guys think.

 

First of all, what muffler is it?

Yes, in general speaking, the shorter the muffler the louder the muffler will be. For instance, if you have a 4x9x18 Magnaflow and you replace it with a 4x9x14, you will notice a significant difference. Interior and exterior volume will be noticeably greater.

As for the 4x9 vs. 5x8? A 5x8 at the same case length will actually be a little quieter than the 4x9. They have more volume in the case, thus, more packing material.

Hope this helps...

 

thanks, avfrog! I had the feeling that's what would play into the noise level was volume.

that helps a lot.

 

it's a Magnaflow muffler btw, either will be a XL or universal, just haven't decided.

 

DO NOT get an XL muffler. These mufflers are chambered and packed. They will diminish what you are trying to accomplish with a performance muffler. Stick with the straight threw designed mufflers. They will perform and sound much better.

 

so the XL line is more or less a stock replacement line from Magnaflow? Thanks for making that clear man.

Looks like I will either be getting a 4x9 or 5x8 in 18" length.

thanks for the help again avfrog