Date: Mon, 3 Mar 1997 21:28:18 -0800
From: Mike West <mwest@CDSNET.NET>
Subject: Re: Velocity Stack question?

>Howdy.
>        I'm wondering, should be running velocity stacks on the 40 IDF's on
>this 1835?  I've been told yes and no?  What are the pro's and cons?
>
>Insight?
- - - - - - - - - - - -

 Give you a couple reasons I have read about, one of the sources is Berg, I
think.

 First a physical law thing: with a funnel you can get more air in there
than without due to the sharp transition of the edge of the
carb mouth. That sharp edge is a pressure drop and probably cuts the
effective throat size by quite a bit. Turbulent flow versus Laminar.

 The second reason is the one I attribute to Berg: he says that there
is a cloud of fuel vapor above the carb opening approximately the height of
the air cleaner (stock).

 If you don't have a velocity stack or tube like contrivance that hi,
you will lose a lot of fuel. Serious mileage difference.

 The various stock cleaners seem to bear this out but I really couldn't
prove it.

 This is not to say a velocity stack over a decent air cleaner of the
proper height, tho if I were racing, I think I would go with the stack.

 west

Re: Velocity Stack question?