Gregg -

While other posts debate the good and bad of stainless hardware (of
which I am in the camp of good ole original 1 time use and not
stainless), no one has really fully answered your size question
adequately.  I offer the following, complete with VW numbers:

Collector to Header Pipe
N01024416  8x30 (13mm Hex) Bolt Qty 4

Collector to Collector Pipe Going to Cat
N01036112  8x65 (13mm Hex) Bolt Qty 3
N90095501  8x15 Flat Washer Qty 3
 Note: Place these on the "nut" side
 Note: I have used N01152520 8x16 Flat Washer
025251200  8mm Concave Washer Qty 3
 Note: Place these on the "nut" side
 Note:  I have used N0122282 8x17 "Wavy Washers"
311101463  8mm (13mm Hex) Locking Hex Nut Qty 3

Collector Pipe to Cat Converter
N01034510  8x45 (13mm Hex) Bolt Qty 3
311101463  8mm (13mm Hex) Locking Hex Nut Qty 3

Cat Converter to Muffler
N01024416  8x30 (13mm Hex) Bolt Qty 3
N01152520  8x17 Flat Washer Qty 3
 Note: Place these on the "nut" side
311101463  8mm (13mm Hex) Locking Hex Nut Qty 3

All above fits 86-91

Exhaust Hardware Class 101 dismissed :)
--
Jim Thompson
84 GL 1.9 "Gloria"
84 Westfalia 2.1 "Ole Putt"
72 411 Station Wagon "Pug"
75 914 1.8 "Nancy"
Full Timing Since March 1999
oldvolkshome@gmail.com
http://www.oldvolkshome.com
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On Fri, Feb 11, 2011 at 1:21 PM, Gregg Carlen <gregg.carlen@gmail.com> wrote:
> On my 90 Westy, I'm planning tomorrow to replace the exaust collector
> (Bentley calls it an Exhaust manifold, P.26.9) along with the 3 gaskets. As
> with any exhaust that's lived past its useful life, the nuts and bolts will
> have to be cut off. Anyone know what the sizes are of the 7 bolts/nuts that
> hold this thing to the associated pipes? Bentley shows them, but I can't
> find an indication of what size they are. I've got to pick some up at FLAPS
> or my local Napa, stainless steel, I would assume if I can.
>
> In case your wondering, I really think its only the donut seal that's bad,
> but that collector isn't looking very good, so I'm just going to replace it
> along with the gaskets anyway. Strangley enough, the rest of the pipes (and
> cat/muffler) look in good shape.
>
> TIA,
> Gregg
> 90 Westy