The packing material eventually gets carboned up some..
reducing the noise ssuppression factor.
  I have nothing against baffle type mufflers.
I do use a glass pack after a diesel turbo though ...seems to last and
work just fine.

On 2/4/2013 9:55 PM, Alistair Bell wrote:
> Neil,
>
> I picked up two 3 foot lengths of the perf tube about 13-14 years ago at a metal scrap yard. Yup, I have been procrastinating about making a muffler for that long. The 6" tubing for the can I got last fall at another scrap yard. The 2" tubing were off cuts from a steam line install in a lab I worked in.... it all adds up.
>
> The stock wbx muffler is a baffle type unit, I think. I wasn't certain that a flow through with packing, like I made, would be quiet enough, but it is. Probably the heavy guage components helps absorb some of the sound/vibrations.
>
> alistair
>
>
>
> On 2013-02-04, at 8:49 PM, neil n wrote:
>
>> Perforated SS pipe? Sounds like an exotic piece of "scrap" to have
>> kicking around.    ;^)
>>
>> Nice work Alistair!
>>
>> Though I didn't make a muffler, I did some more exhaust fabrication
>> recently. Suffice it say, I really appreciated what you've done!
>>
>> Is the stock WBX muffler of a similar design?
>>
>> Neil.
>>
>> On Mon, Feb 4, 2013 at 6:36 PM, Alistair Bell <albell@shaw.ca> wrote:
>>> This last weekend I finally realised a dream of a lifetime :) Yes, I installed my homemade muffler in my van. Pics and a wee video with sound here:
>>>
>>> http://shufti.wordpress.com/2013/02/04/vanagon-home-made-muffler-installed/
>>>
>>> alistair