The exhaust provided by David Marshall at www.fastforward.ca is shown below.  I believe the pictures speak for themselves as far as to why I didn’t use it.  With tiny downpipe tubes, that are too short and result in unequal runner lengths, and a K-car muffler that is very restrictive, this would easily cost 10 or more HP and a few MPG.  I’m sure it’s quiet though.  If anyone wants it, you’re welcome to the manifold for $50.

  How not to design a header pipe.  Beside the fast forward downpipe is the Audi 80 downpipe.  You’ll notice a large difference in tube diameter.  The Audi has 1 ¾” inner diameter tubing which is the ideal size for 2.0 Litre VW engines.

  Initial calculations on header tube length (including manifold) and size were made from here http://www.bgsoflex.com/auto.html  Essentially I’ve used lengths and sizes similar to a Techtonics downpipe for this type of engine. 

  The manifold Darrel at Techtonics suggested was the Audi 80 dual outlet, which I see is also favoured on the listserve.  I found a scrap downpipe from the same vehicle, basically just to get the manifold to header pipe flange.  Below is the fox manifold compared to the Audi 80.  The Audi manifold has a much larger flange and 1 ¾” (bigger) outlet ports.

  My solution to the issue of breaking header pipes was to incorporate two (overkill) stainless flex joints from JC Whitney.  The tubing is mandrel bent aluminized steel that I’ve cut and welded to form the header pipes, and connections for the cat and two mufflers.

  I researched mufflers http://www.autospeed.com/cms/A_0383/article.html and ended up buying two Genie straight through mufflers/resonators.  The cat is a high flow stainless unit that I purchased from our local speed shop for $90 CAN.  Muffler 1 (5 inch) is a GENIE straight through stainless and muffler 2 (six inch) is a straight-through Magnaflow.  They were $135 CAN each.  The O2 bung was purchased locally.   The tailpipe is a mandrel bent 90 degree bend purchased from the local speed shop and polished a bit to make it pretty.  I’ve modified the stock vanagon muffler straps and mounted them with rubber isolators similar to the diesel vanagon.  I will likely convert these to conventional hangars at some point as the mounts are a bit wimpy.  They do however dampen vibration well.

  Here are the original two Genie http://www.marcor-genie.com/mufflers.htm mufflers I used.  The muffler on the right was later replaced with a 6 inch muffler (OD) (similar to the resonator on the left) to bring the noise level

       

  Ceramic coating is Black Satin available from http://www.techlinecoatings.com/Exhaust.htm which was air sprayed onto the sandblasted exhaust.  The product fully cures after air drying compliments of the exhaust heat.  The manufacture claims 2000F  tolerance, as well as significant reductions in radiated heat.  So far I would support these claims as far as tolerance but with the exception of not actually monitoring radiated heat before and after coating.  Ceramic coating is used commonly in aerospace where heat tolerance is required so I'm guessing it works.

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