Hey Don.

I'm pretty sure the 1.6 NA diesel Vanagon engine downpipe bolts right
up to the exhaust manifold. Regardless, yes! I do recall those pesky C
clips. My '81 diesel Rabbit had them; it used the toilet bowl design
IIRC. My guess is that the 1.6 NA in a Vanagon doesn't need these
parts since the exhaust is bolted to the engine (with isolators of
course)

I recall posting this to the I4 list, but I found a few thesis's on
exhaust design. The general gist of these is shown here

http://www.openthesis.org/documents/Dynamics-Study-Automobile-Exhaust-System-597672.html

and some or all of the thesis' are here (large pdf file!):

http://www.bth.se/fou/forskinfo.nsf/0/d8c7e9e257698dacc1256fae003cebf7/$FILE/Lic_JWL_FOU.pdf

But I digress.

The 2 brackets I made are robust and very similar to the diesel
Vanagon design. In particular the drive side with the Bosal DV
perpendicular and ~ 45� isolators as Scott refers to. The added arm
for the cat is also robust but supporting the cat with a 5" exhaust
clamp may not be a great idea over the long term. Maybe pressure
exerted by the clamp, and any stray engine vibrations over the long
term would cause the cat body to crack? As per Dennis Hayne's
suggestion a while back, I would have made a bracket to the cat
flange, (inlet) but that makes for a long arm.

Neil.

On Fri, Dec 21, 2012 at 6:20 AM, Don Hanson <dhanson928@gmail.com> wrote:

>   Neil, the diesel vanagon exhaust downpipe uses a 'toilet bowl' type flange
> in place of a flex section.   I suppose this +might+ allow for some movement
> to relieve stress, but I always figured it was like that only to make the
> system almost impossible to remove and install....*grin*....perhaps with
> some special tool it's a snap...(pun).   When I had that system on my inline
> gas motor it was the very hardest part of working on that motor....The "C"
> clips that were holding the round end of the exhaust downpipe into the
> bowl-shaped manifold, those things would "sproing!" across my shop if I got
> even slightly crooked with my pry bars and clamps as I tried to work on that
> nasty set up.    On an aside, the diesel 1.6 na. manifold has tiny inside
> diameters and is very restrictive.
>
>    Your install is new-ish territory.   With the cat and at 15deg rather
> than at 50deg...not many of those running, so there isn't any tried and true
> way.    The FAST auto new-style set-up that has gotten recent discussion by
> the Tiico crowd....it *might* work...it has to be better than the 1st Gen
> Tiico ones that everyone has problems with...Key word is "might" since they
> haven't been around long enough for real world durability to show yet.
>
>    I'd go with a system mounted to the engine only.   That seems to be the
> most successful and widely-accepted way to do in inline exhaust in the
> vanagon.    I would not use a flex section.   As I have evolved my own
> inline exhaust systems I have had those sections crack and split....they are
> weak....I don't think they are needed..They aren't there on the diesels and
> quite a few gas conversions have been on the road for years without them, I
> read on the net.
>
>    Don Hanson
>
> On Fri, Dec 21, 2012 at 12:07 AM, neil n <musomuso@gmail.com> wrote:

>> My engine is mounted at 15�, and I'm running a cat so the space

-- 
Neil n

65 kb image Myford Ready For Assembly  http://tinyurl.com/64sx4rp

'88 Slate Blue Westy to be named.

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Vanagon VAG Gas I4/VR Swap Google Group:

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