Hey Jim.

Thanks for the insight into the design terms/math. ( I was wondering
what a "3.5" radius" referred to when viewing 180 degree "J" bend pipe
online)

It's a 4-2 exhaust manifold.

I might be using the wrong terms.

By "collector" I meant the two pipes that come off the manifold, then
merge into a "Y", which then has a short 2" pipe. It's a "Y" pipe. I
have also referred to this as the "downpipe". Anyhow....

I cut off the flange, that bolted to the manifold, from the Jetta
downpipe. I cut the downpipes roughly in half. The plan is to weld a
90 degree elbow to each port on the flange, take those to a remaining
half of the downpipe (which incorporates the collector) then use 2"
from the end of the collector to the cat and muffler.

If that makes sense. I should "draw" up a picture.

On Thu, Mar 27, 2008 at 9:28 PM, Jim Akiba <syncrolist@bostig.com> wrote:
> So wait Neil you're building from the head all the way down or just
>  from the collectors down? You said "90 deg pipes" plural from
>  "manifold " to collector... are you referring to primaries from the
>  exhaust flange to the collector there? Or it the jetta system a 4-2-1
>  style exhaust or something?
>
>  With mild steel you should be able to find 1.5D bends(1.5x the
>  diameter of the tubing, which yields a 3" CLR or center line radius
>  which is how "tight" the bends are).
>
>  Jim Akiba
>
>
>
>
>
>  On Thu, Mar 27, 2008 at 12:01 PM, neil N <musomuso@gmail.com> wrote:
>  >  Short run of 1 5/8" 90 degree pipes from manifold to collector, then a
>  >  "J" pipe forward, around, and back to stock Vanagon cat and muffler.
>  >  OR an aftermarket cat and muffler with 2" inlets/outlets.
>  >
>  >  After the collector, the Jetta is 2" pipe.
>  >
>  >  What is the diameter of exhaust pipe on the Vanagon?
>  >
>  >  Can anyone direct me to a quiet good sounding, good fitting after
>  >  market muffler?
>  >
>  >  And how "tight" a bend can be made (mandrel bent) on 2" aluminized steel?
>  >
>  >
>  >
>  >  Thanks!
>  >
>  >  Neil.
>  >
>  >
>  >
>  >  --
>  >  Neil Nicholson. 1981 Air Cooled Westfalia - "Jaco"
>  >
>  >  http://web.mac.com/tubaneil
>  >  http://tubaneil.googlepages.com/
>  >
>

--
Neil Nicholson. 1981 Air Cooled Westfalia - "Jaco"

http://web.mac.com/tubaneil
http://tubaneil.googlepages.com/