In a message dated 1/19/12 11:28:44 AM, healeys-request at autox.team.net
writes:
> He got better performance with a couple velocity
> stacks on the carbs. Dunno if he proved it with a dyno or track times,
> but he
> was
> convinced.
>
Ah, there's the rub -- you can't prove one or the other by dyno testing, OR
by track times. The first doesn't work because there's no air flow on a
dyno (other than induced by a BF fan, and that isn't accurate). Track times
don't work because of the multitude of other variables. The closest you'll
come
is the Menadue Method. You have a straight even slope behind the works that
allows you to run the car at speed, under load in a controlled setting.
(Incidentally, there was just such a ramp/hill constructed at Brooklands, for
just that purpose. It's still there.) You run the car up the hill against the
clock, make one change, and do it again. Reduced time -- right direction;
increased time -- wrong direction. That's how they set the timing and made
all the other changes that improved performance.
Gary
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