OK, that makes sense. In my defense I should note that I never passed physics.
There was, like, math and stuff in it. Yuck!
Chris Eck
59 Bugeye
> ----- Original Message -----
> From: <ckotting@wideopenwest.com>
> To: <spridgets@autox.team.net>
> Sent: Tuesday, January 07, 2003 3:28 PM
> Subject: RE: Ugh
>
>
> > Longer connecting rods DO increase compression, but they
> > reduce displacement. Maybe some ascii art will help:
> > ___ ___
> > Combustion chamber ___| |___ ___| |___
> > | | |___| Piston up
> > | | | | |
> > | | | | |
> > | | | | |
> > |___| | | |
> > Piston down | | | | | |
> >
> > (Assume that the diameter of everything is constant)
> > Swept area of piston = 4
> > Compbustion Chamber with piston up = 2
> > Compression ratio = 4:2 or 2:1
> > Displacement (Piston Sweep + Combustion Chamber) = 6
> >
> > Longer conrod moves "stroke" of piston higher (as you
> > noted):
> > ___ ___
> > Combustion chamber ___| |___ ___|___|___
> > | | | | | Piston up
> > | | | | |
> > | | | | |
> > |___| | | |
> > | | | | | |
> > Piston down | | | | | |
> >
> > Swept area of piston (still) = 4
> > Compbustion Chamber with piston up = 1
> > Compression ratio = 4:1
> > Displacement (Piston Sweep + Combustion Chamber) = 5
> >
> > Now, nobody increases the conrod length by 1/4 of the
> > stroke, but you get the idea...
> >
> > A longer crank journal (with the same conrod) increases both
> > compression AND displacement (sweep of the piston goes lower
> > down AND comes higher up). That is why "stroker"
> > crankshafts are usually supplied with matching conrods (a
> > touch shorter than stock to keep the compression from
> > becoming insane).
--
Chris Eck
59 Bugeye
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