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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