U20 fuel pump spec/data

[cromgnman]

I am looking for data on the output pressure and flow rate of a U20 fuel pump?

[Gregs672000]

I don't know what the flow rate is, but the mechanical pump probably runs around 3-5lbs. I use a generic "Mr Gasket" electric pump that's set for 3-4lbs and it feeds my modified U20 no problem. For me, what's important is that it doesn't overwhelm the float valve in the carbs as fuel level impacts fuel ratio in most sidedraft carbs (Mikuni, Weber, Dellorto, etc). That's why they have different pressure ratings in the family of pumps made.

[jhayden]

Per page 51 of Nissan Service Manual: (all measurements @700rpm)

Cap’y: 800cc in one minute or less
Vacuum: 500mm min hg
Pressure: 0.24 to 0.3 kg/cm2

(BTW, Hitachi/SU carbies as mounted on 311s are also sidedrafts/sidedraughts)

Fully agree w/Greg on importance of not too much pressure

Jon