The O2 sensor needs to be before the Cat. Flex couplings and floating
exhausts work for vehicles as the have long exhaust systems. The short
system on the Vanagon is best to be fully mounted and allowed to move with
the engine. Also, avoid having the cat and O2 sensor directly behind the
tires. The thermal shock from road spray is not good and will foul the
sensor.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
neil n
Sent: Saturday, December 22, 2012 3:00 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: [Diesel-Vanagon] Re: Diesel Vanagon Exhaust Design

On Fri, Dec 21, 2012 at 1:59 PM, Scott Daniel - Turbovans
<scottdaniel@turbovans.com> wrote:

> Hi Neil,
> 'usually' ...the cat is mounted to the upstream side of the muffler..
> and the whole works, cat , muff, and tail pipe go across the back of the
van.

This is how I mounted my exhaust

> or you could have a short cat running fore-aft ...then the pipe coming out
of that curves to meet the muffler across the back.

had been thinking of doing that. Image of my mock up:

https://lh6.googleusercontent.com/-sIC-CuoXFrw/UNVnbPyYPXI/AAAAAAAAGas/LYApn
_HMsXk/s720/Cat%2520Mockup.jpg

> Re that comment , 'newish territory' ..
> as I said, it's not. VW built Bay Buses in Mexico with absolutey upright
inline four engines in the back.
> I have seen one in person in Mexico, new at a dealership in Peurto
Vallarta.
> Those are no longer in production.
> So ..go online ....and find diagrams of how VW did in that vehicle.
> I would not be suprised if they transisioned from 'engine-to-body' the the
exhasut ...muffler and cat being body mounted ..or hung from the body ..
> though I'm not a big fan of rubber donuts to hand the exhaust from ...
>

good idea!   I have seen images of the Bay Bus 1.4 engines but not of
the exhaust. I'll look around.

Neil.

--
Neil n

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

'88 Slate Blue Westy to be named.

'81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/

Vanagon VAG Gas I4/VR Swap Google Group:

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engine
s