Date: Fri, 28 Mar 2008 13:02:43 -0700
Reply-To: "Jim @ work" <jrasite@EONI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Jim @ work" <jrasite@EONI.COM>
Subject: Re: Vanagon exhaust diameter? + Custom exhaust fabrication
questions.
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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/
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