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RE: rod length

To: "'kas kastner'" <kaskas@cox.net>, riverside
Subject: RE: rod length
From: Bill Babcock <BillB@bnj.com>
Date: Tue, 14 Jun 2005 15:32:41 -0700
I don't either, but I like it. It's kind of Zen.  


Bill Babcock
Babcock & Jenkins

-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net] On Behalf
Of kas kastner
Sent: Tuesday, June 14, 2005 12:27 PM
To: riverside; fot
Subject: Re: rod length

Given that this turns out to be a terrific thing, what makes you think
you'll ever hear any results from the developer who took a chance and spent
his time and hard earned cash?

 "If you have a truck full of melons and start giving them away until they
are gone, then all you have is an empty truck" ( I have no idea what this
has to do with anything)
  ----- Original Message -----
  From: riverside
  To: fot
  Sent: Tuesday, June 14, 2005 2:05 PM
  Subject: rod length


  This topic used to cause me brain damage, but long ago,
  i too made peace with it.

  issue #1.  we are denied the advantage of building race motors from
  a clean sheet of paper.  Our deck height is set.  New F1 engines have
  rod/stroke ratios of well over 2:1.  Few street engines come that way.
  V12 Jag is about 2.16.   259 Stude V8 is 2.11   Most are about 1.7 because
  they were designed that way for a whole lot of reasons not related to HP
  production.
  the point is that we are severely limited.

  #2   HRM is imho a poor source of race engine science.  I seem to remember
         a similar article about 5-6 years ago where they did get
significant
         changes in HP with only rod and piston change.    above 5KRPM
         i doubt that there is much cam difference, but below 4K there would
be
         alot of diff since the one advantage of a short rod is its ability
to
  get a
         stopped column of fluid moving better that the long rod.   Frankly,
in
  a
          race engine, I can't see this as a plus.


  #3    The business with dwell time and rod angle advantage can be best
  understood
          by those of us who are conceptually impaired  ( hell, it took me
years
  to
          understand how "caster made you faster")  by making paper dolls.
          use some stiff paper to make models of two setups.  Make one about
  1.5:1
          and the other about 6:1.  an absurd example often best illustrates
  the
          concept.  the change in dwell time will be noticeable.

  #4     Is this "worth the time/money"?   Maybe we will find out,
especially
if
  someone
           really goes whole hog with modern short compression distance
pistons
  so
           the longest rod possible gets squeezed in.
  art d

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