I think Keith's reason for big bore small stroke is to create sufficient
bore diameter to allow for the big valves he has for better breathing. I
guess the thought is that better breathing makes more HP.
John Beckett, LSR #79,
----- Original Message -----
From: "Jane McMeekin" <jmcmeekin@worldnet.att.net>
To: <land-speed@autox.team.net>
Sent: Thursday, October 19, 2000 11:21 AM
Subject: Bore/Stroke Ratio
> Talking about a "favorite" Class "D" engine size makes me wonder if an
> ideal bore/stroke ratio exists in terms of maximum power potential. Big
> bore, big valve condition aside, should we expect a significant power
> differential between a 4.25"x2.65" ratio and a 4"x3" size? Is the
> primary reason for favoring the larger bore due to "better breathing" or
> do piston speed, friction, and other variables enter into the equation?
>
> Incidentally the 3 Liter Buick has a 3.52x2.35 bore and stroke with 6"
> rods. Our "fanny dyno" says its doing all right but maybe it could be
> better.
>
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