Date: Sun, 9 Feb 2014 19:32:17 -0800
Reply-To: "SDF ( Scott Daniel Foss )" <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "SDF ( Scott Daniel Foss )" <scottdaniel@TURBOVANS.COM>
Organization: Cosmic Reminders
Subject: Re: Exhaust Bushing Inner Weave Premature Failure
In-Reply-To: <CAB2RwfiUQFKLxvhRvss0NVnJH9p5dg5NmM-qr+SCLwo3n8+6dg@mail.gmail.com>
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As I've said..
I just reproduce what VW did with their diesel vanagon ..
and that includes having the down pipe do an S curve down ....and then
near the engine..
then doing a big U turn to enter into the cat and muffler. It's an S and
not in one plain.
look at the header / down pipe for a diesel vanagon .
it could very well be that those curves and U-turn absorb vibration
related stresses.
I just do the same thing but bigger.
and for sure ..a 3 bolt flange at the end of the header/down pipe ...
then cat, then flange again, then tail pipe, with all those across the
rear of the engine and van .
it's much harder to do than a simple straight-with-curves at the corners
pipe..considerably more labor intensive to fabricate ...sure seems to
work though.
I've had excellent results by building the pipes n' stuff in place on
the van ..
usually fit in place, weld some, remove, weld some more, re-fit to check
things etc..
several times, spending hours even.
and I don't try to make my welding perfect.
after I have it well tack-welded together and perfectly fitting , then
I take it to a real welder-fabricator and have him finish-weld it ..
that's always worked just great.
in welding ..the actual 'zzzzzzt't welding part is nothing ..
it's the design and set up that's the hard part.
when you hand something to a welder and say 'weld this please' ..and
there's nothing for them to figure out , or clean , or fit ..just zap it
carefully ... ..that's super easy for them and they usually don't charge
much.
My style is to incrementally move something towards the final
configuration ..in careful steps ..
it takes lots longer that way, but the result is often quite good.
lol..I've seen a tdi exhaust on van ..looked at how it was done and
figured 45 minutes at the most is all it took ..
and one ..while quite crude, I could see that it was going to work for a
good while, especially considering the very low effort and time it too
to make it. I spend a good dozen or more hours making mine ..but they
come out pretty darn good. I do it for the reward and satifaction too
..not just to get something that works.
scott
was turbovans
On 2/9/2014 6:06 PM, Neil N wrote:
> I bet!the
>
> Scott and Alistair have had great success building I4 exhausts with no
> flex joint so when the current bushing fails, I'll replace the section
> with pipe. The cat hanging out away from the engine may not be the
> best bet but we'll see. In hindsight, I should have made the cat
> serviceable with bolt flanges at each end.
>
> Someday soon I hope to tilt my engine over to the 50ยบ mount angle but
> am in no hurry to do so.
>
> I wonder how much of the old bushing weave is stuck in the element?
>
> I appreciate the help and "list patience" with this thread. Thanks folks!
>
> Neil.
>
> On 2/9/14, Dennis Haynes <d23haynes57@hotmail.com> wrote:
>
>> Five inch exhaust can make you
>> appreciate Vanagon exhaust quickly.
>