Jim Cate wrote:
As far as cruising speed in typical ( e.g., 15 - 20 knot) winds, under
full normal jib and main, average load, and equally experienced
captains, etc., would there be a significant difference in speed or
handling between the Cal and O'Day, both being in good condition and
similarly equipped?

To put the PHRF ratings already quoted into perspective, those numbers
are commonly equated to seconds per nautical mile. Lower is faster. So
if the O'Day rates 147 and the Cal rates 167, on very broad average
including all points of sail, the O'Day will be 20 seconds ahead for
every mile the two boats sail.

Please not that there are a lot of variables and there are conditions
where the Cal might be ahead of the O'Day, but that's what the ratings mean.


... The (1978) Cal 34-III has a waterline of 26 ft, and
the (1983) O'Day has a 28'9" waterline, according to the spec sheets.
Plugging this into the formula (square root of wl times 1.34), I get a
predicted hull speed for the O'Day of around 7.185 knots, and 6.833
knots for the Cal.

Hull speed makes more difference motoring than sailing... the one
exception is reaching in moderate wind, when the hull shape, sail
carrying power, effects of waves, helm characteristics, etc etc, are not
in play.

Fresh Breezes- Doug King