Brian Hollands wrote:
> Both are wrong. The SU's on the 2000 are 46mm. To be exact, the carbs are
> Hitachi HJG46W's. The number in the carb type indicates the throat size.
> 44mm are the Solex's - but they of course have 4 throats total so flow a lot
> more air than the SU's. The 1600 carbs are 38mm.
Brian is right. I may have caused this confusion when I typed 44 in a
post not too long ago. They are 46s.
However the flow issue isn't quite so straight forward. If you run all
the carbs through a single plenum, then yes, a pair of
Solex/Mikuni/Weber/SK/Dellortos will flow more than a pair SUs. However
they don't do that. The Solex/Mikuni/Weber/SK/Dellortos are on
individual runner manifolds, that means each cylinder is drawing through
a single 44mm throat (45 for Weber). The SUs each feed two cylinders,
but each carb is feeding only one cylinder at a time, so functionally
each cylinder is feeding through a single 46mm throat. Now it is a bit
more complex than just that, because of distribution issues and manifold
flow, etc., but the bottom line is that the benefits of the
Solex/Mikuni/Weber/SK/Dellorto carbs has less to do with improved flow
or being bigger, and a lot more to do with controlling distribution,
keeping fuel in suspension, and shortening reaction times in the intake
system. Knowing that each cylinder flows through a single throat, no
matter which carb type you run, you can flow just a single throat and
get a better (though still not accurate) idea of how different carbs
will compare in terms of flow.
--
Marc Sayer
Journalist, Photographer, Dog Trainer (APDT member #062956)
Passions -
Great Danes, auto racing and fast cars, my wife
Dogs -
Gracie, Tank, Delilah, PJ, & the rescue dogs
Cars -
82 280ZX Turbo, 71 510 Trans Am vintage racer, 93 Ford E150 Tow/dog van
My Homepage - http://gracieland.org
Deaf Dane Rescue Homepge - http://gracieland.org/DaneRescue/
Any Dane at the races is a Great Dane!
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