Very interesting. Ok. I'd sized my generic cat for x.x litre engine
etc. but obviously didn't even think of higher sustained RPM's.

I see the stainless steel GW muffler you refer to. Thanks. A bit
spendy for me but we'll see what I use on my next engine swap.

Neil.

On 7/2/17, Dennis Haynes <d23haynes57@hotmail.com> wrote:

> Most mufflers for the vanagon have some form of baffles and tubes and it is
> common for them to get plugged up by pieces of catalyst. One advantage of
> the GoWesty muffler is the straight through design.
>
> As for the catalyst failing there is a reason those aftermarket cats are
> becoming illegal in many areas. They don’t last as long as they should nor
> perform as they should. In your case things are possibly worse due to your
> choice of engine. As it works under more of a load and at higher RPMs the
> cat is tasked with reducing the increased NOx emissions of that combination.
>  Of the aftermarket cats I have seen the Walker probably has the most
> restrictive and shortest gas contact time of any of them. I used to use the
> Emico as it was a well-made unit still reasonably priced. Now that I'm in an
> area that requires OEM or CARB approved I use the GoWesty due to their
> support and price.
>
> Dennis

-- 
Neil n

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