ALUMINIUM SECONDARY BYPASS HIGH FLOW – SUIT ALL FUELS

Description

Standard 6 AN male flare
hard anodized aluminium valve,
complete assembly, includes:
poppet, spring, and shims, for
gasoline and methanol. Since
the engine makes less power at
part throttle, it needs less
fuel. The spool in the barrel
valve is the main control for
part throttle fuel delivery.
At wide open throttle, the
spool has a large notch cut
into its side to pass all the
fuel to the nozzles
unrestricted. As the throttles
are closed, a tapered ramp
ground into the side of the
spool reduces the passage to
restrict flow to the nozzles.
When adjusting the hex-link to
set the idle fuel rate, the
spool is being re-positioned
to make the passageway larger
or smaller to the nozzles. If
you remove the fitting from
the top of the barrel valve,
you can see this ramp. Because
each engine’s part throttle
fuel requirement varies due to
camshaft, manifold, and
exhaust system selection, the
fuel rate the ramp delivers at
part throttle is seldom
exactly what the engine needs,
but the secondary can be used
to tailor it.