RE: 40 vs 45

["Brian Shorey" <bshorey@domain.elided>]

> I concur with the poster who suggested ajusting venturi size for intended
> use. I have SK 47mm racing carbs on a 2L using 38mm (if memory serves)
> venturis. This is a street engine with stage V heads, mild cams and
> Shankle headers. Somewhere there is a chart which tells how large the
> carbs need to be for displacement vs rpm.

another data point for the discussion,

i've got 48mm dellorto's on my spider, 2 liter motor with quite a few mods.
i normally run with 36mm venturi's, but tried 41mm venturi's one year at
lime rock.  although i had more power at 7k rpm (and above), i lost all my
low end torque coming out of the corners and the result was lap times about
a second a lap slower.

fwiw,

bs, who's got spica and carbed alfas (and bosch..)

------------------------------