"Ronak, TP (Timothy)" wrote:
> Ok everyone,
> In plain English.....I am interested in knowing if the extra friction,
> stroke and cubes generated by the stroked motor outweighs the advantage of
> having a longer rod with a shorter stroke and less cubes and less frictional
> heat for RPM potential.
I'll take one shot at this, as I've stayed out. I think that the stroke/bore
ratio has been studied for some time, and the only people who never got it tight
were the English, as that was a Tax question.
For whatever it's worth:
Square, or slightly over square engines (same or larger bore than stroke) reduce
the piston speeds and friction at any rpm. I recall the Road and Track criteria
for good design and efficiency was to be able to have a good highway constant
speed at 2500 feet/minute piston linear speed. They published the speed at 2500
fpm in every road test.
So, if efficiency and life expectancy are a criteria, I'd have to go with this.
I
do know that some new cars are gravitating to longer strokes, but I believe this
is a manufacturing and number of stocking parts issue, rather than a design
preference.
Dick and Tim, I hope this brings the discussion down to a simpler conceptual
level.
--
Steve Laifman < Find out what is most >
B9472289 < important in your life >
< and don't let it get away!>
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