The problem is not to much fuel, but rather low air speed. From what I
understand the fuel that does enter the airstream also tends to cling to the
intake runner walls as it does not atomize well. That is why the accelerator
pump on a traditional carburetor adds fuel and sprays it into the airstream
in an attempt to mix it with the air.
Gregg Robinson
'70 1600
McMinnville, OR
-----Original Message-----
From: owner-datsun-roadsters@autox.team.net
[mailto:owner-datsun-roadsters@autox.team.net]On Behalf Of B Strachan
Sent: Sunday, March 19, 2000 12:47 PM
Cc: a roadster list
Subject: Re: SU goo
> The damper oil, variable venturi and dashpot act as a reverse
> accelerator pump. Vacuum opens the venturi, and the needle below
> adjusts the fuel flow accordingly. The problem is, when you pop the
> throttle open, vacuum spikes instantly, opening the venturi, but the
> engine takes time to spin up and draw large volumes of air. The oil
> controls the opening speed of the venturi, preventing the dashpot from
> rising too fast and dumping a bunch of gas into the (still
> slowly-moving) intake air.
I'm not sure I believe this. Looked at an acceleration pump on a Solex
lately? They do exactly the reverse - dump a whole bunch of gas in the
manifold the instant you open the throttle.
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