Port Nozzle Bodies

Digging through my stuff I came across this set of port nozzle bodies.

They have a square slot cut in them on each side that goes up to where the nozzle threads in.

Not sure what they were used for ?

Jeff

 

They are nozzles that are aerated from manifold pressure.

 

How does the manifold pressure get into the slots? Looks to me like a slot to provide additional fuel flow. Just my thoughts.

 

How about these nozzles originally have a spring/check in them, and these slots were used to dribble a little fuel before the check opened?

 

The part of the nozzle past the threaded area is smaller than the threaded hole in the manifold and therefore exposed to manifold pressure. It feeds up into the cavity above.

 

Identical pressure on both sides of an orifice negate each other resulting in no effect to the flow, no additional atomization.

 

Looks to me like someone's idea that did not turn out well or these nozzles would be commercially available.

 

Then why do conventional aerated nozzles intended for use in the hat produce better atomization than non-aerated.. even when tested on a flow bench with 14.7 psi (atmospheric pressure) on both sides ?

 

Vacuum
Oh, you are saying visually they look better on the bench.

 

Yes Dave.. side by side with non-aerated they will show better misting.

 

Venturi effect, the fuel flowing through the nozzle creates a vacuum pulling air in through the hole

 

We have a winner ! That's exactly what's happening Nitro Diver. You can hear the vacuum on the bench and feel it with your finger There's reduced pressure in the cavity that the fuel flows through, which is why those nozzles will work as advertised.