Re: ihc-digest V5 #231

[jmbrodsky@domain.elided]

Tom, Terry,

     When I had my 3" done on the T'all I did some calcs with the 
Fluids books and found the following.  Since exhaust from an auto 
is low Reynolds number flow (low viscosity, low velocity) the 
skin friction is a factor, due to boundary layer development.  
Well, 1/2 hour tech talk subtracted, 3" exhaust gives you less 
skin friction dues to smaller surface area than 2x 2-1/4 pipes, 
and has a higher x-Area/section than the duals.

And it was cheaper, and with the single 3" Dyno max muffler it 
came to $300 even.  Also the single 3" is all on the left side 
and it avoids the annoying crook around the T-case.

FWIW,

     -Joel Brodsky

         '76 IHC Scout II 345/tf727
         '75 IHC Travelall 150 4wd 392/tf727
         '72 Chev Carryall 3dr 4wd 350/th350 sold, but not forgotten.

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Date: Tue, 03 Mar 1998 09:24:44 -0500
From: tsm1@domain.elided (Tom Mandera)
Subject: Re: Exhaust?

>originally thought that a typical dual system would be the way to go but I
>seem to remeber some talk here about a single 3" system being the optimum.
>Sarah wants it to be quiet, but I think a little bit of " Whoa!, a V8"

Terry,

I don't know if the single 3" is "optimal", but I finally got a chance to
crawl under my '72 last weekend (after 9 or 10 months!) and took a peek at
the exhaust.
<SNIP>

- -Tom Mandera, Helena MT
http://www.tmcom.com/~tsm1/scout
'72 Scout II - 304V8, 3.73s, and lots o' work to be done
'77 Scout II - 196, 4.09s, Track-lok, 31s, 4" Softride, air

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