Thanks for the link Jim!

Neil.

On Fri, Mar 28, 2008 at 1:02 PM, Jim @ work <jrasite@eoni.com> wrote:
> Phillip K Smith's The Scientific Design of Exhaust and Intake Systems.
>
>  http://www.amazon.com/Scientific-Exhaust-Systems-Engineering-Performance/dp/0837603099
>
>  Order through: http://wetwesties.type2.com/amazon.html and WetWesties gets a
>  little bump from Amazon.
>
>
>  Jim
>
>  ----- Original Message -----
>  From: "neil N" <musomuso@GMAIL.COM>
>  To: <vanagon@GERRY.VANAGON.COM>
>
>
> Sent: Thursday, March 27, 2008 8:50 PM
>  Subject: Re: Vanagon exhaust diameter? + Custom exhaust fabrication
>  questions.
>
>
>  > Thanks for the info Kim. I suspected it would be a poor idea to reduce
>  > the ID of the Jetta pipe down to a Vanagon cat/muffler.
>  >
>  > I will stick with a 2" ID on pipes after collector. The collector
>  > itself (Jetta) has 1 5/8" pipes.
>  >
>  > The only real technical stumbling block right now, is that the
>  > collector will be shorter than the stock Jetta. The overall length of
>  > the system will likely be shorter than the stock Jetta, so that
>  > technical aspect I have to ignore.
>  >
>  > At this point, I'm flying blind in a way. I'm sure I could weld the
>  > parts together, but collector length, well I'm learning. Next thing to
>  > find are some 90 mandrel bent elbows. I was able to save the flange
>  > from the Jetta down pipe, so I'll weld the 90's to that then to the
>  > collector, and so on.
>  >
>  > Maybe Mr. Google will yield some info on collector lengths etc.
>  >
>  > Neil.
>  >
>  >
>  >
>  > On Thu, Mar 27, 2008 at 8:16 PM, Kim Springer <kimspringer@rcn.com> wrote:
>  >> Neil,
>  >>
>  >>  Pay attention to the stock system and consider using the same diameters
>  >> and
>  >>  lengths of pipe.
>  >>
>  >>  Exhaust systems are designed for length to the collector, from the
>  >> collector
>  >>  to the end of the exhaust pipe and the diameters of each of these pipes.
>  >> For
>  >>  that matter, the length of the intake is designed to tune the engine as
>  >>  well.
>  >>
>  >>  I have book on tuning 4 stroke engines and another on engine design. The
>  >>  second is extreemly engineering technical, the first has pretty basic
>  >>  formulas for designing an exhaust system based on displacement, valve
>  >> size,
>  >>  etc. If anyone is interested, I'll dig it up. In my aircooled days, I
>  >> used
>  >>  the books to compare off the shelf exhaust system and to choose velocity
>  >>  stacks for my Weber carbs.
>  >>
>  >>  Maybe, for a stock engine, this is overkill, but if you are going to go
>  >>  through the process of building a custom system, you might as well
>  >> enhance
>  >>  the system or build like stock.
>  >>
>  >>  Kim
>  >>
>  >>
>  >>
>  >>
>  >>  ----- Original Message -----
>  >>  From: "neil N" <musomuso@GMAIL.COM>
>  >>  To: <vanagon@GERRY.VANAGON.COM>
>  >>  Sent: Thursday, March 27, 2008 8:01 AM
>  >>  Subject: Vanagon exhaust diameter? + Custom exhaust fabrication
>  >> questions.
>  >>
>  >>
>  >>  > Hi all.
>  >>  >
>  >>  > I'm gathering parts to fab up the exhaust for my Jetta conversion. My
>  >>  plan:
>  >>  >
>  >>  > 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/
>
>

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

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