As far as I know (very little) the muffler chamber is designed with a specific capacity that provide a designed amount of back pressure with increases HP. If you change the volume of the chamber you alter the back pressure and the HP.  That's how it was explained to me

Jere
90 GL
88 GL
  ----- Original Message ----- 
  From: Paul Borghese 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Monday, December 18, 2000 9:32 PM
  Subject: Very dented muffler from Bus Depot

  I just received my brand-new muffler from Bus Depot.  I opened the packaging which is the typical Bus Depot packaging (looks like they went rummaging through someone's garbage to find a box) only to find my muffler at the very bottom of the box, unprotected.  The muffler now has a series of very large dents.  So what do you guys think?  Should I send it back?

  [Rant mode on]
      I love bus depot but why the hell can't they just purchase new boxes?  Every time I order something it arrives in a beat-up old box with wrapped newspaper instead of proper filler!  You can purchase a new box at a manufacturer for under 75 cents! ( I know because the last time I moved I purchased all new boxes).  I would gladly pay 75 cents to have my $140 order shipped correct.  

  [Rant mode off]

  Will the dents effect performance?  There is also a slight rattle in the muffler as if a small rock is lodged in it.  

  Thanks,

  Paul

  P.S. Don't get me wrong, I love Bus Depot and have ordered over $2000 in stuff from them over the years.  I am just a little miffed about waiting two weeks only to find that my van might be down much longer.

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