Will a fuel pump with a rating of 1.5 to 3.5 psi be sufficient for a Datsun 1200 with the Hitachi carb?(Motor is stock)

I had that spec somewhere and now I can't seem to find it.

Thanks!

more than enough

For an A12, the nominal spec is 2.6 lbs.

For a 1980 A-series, the spec is between 3.0 and 3.8 lbs over a variety of engine speeds. This covers A12, A14 and A15 engines. It says if it is below 3.0, replace the fuel pump.

So I'd say 1.5 lbs is not enough. I don't know what the weber specification is, but I doubt if it is too different.

i'm figuring that the low fuel usage of the engine will keep the fuel pressue in the 3.5 lb range.

i have en efi pump from my turbo motor, with malpassi fuel reg running 3psi and the motor has no troubles with that, sometimes the pressure gets higher, around 6psi. maybe the tank gets too much pressure and cant regulate properly but back to the story that pump should be fine.

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im running twin webers on a15 at 1.5psi. using a 4-6 psi elec pump and a regulator (like redline). runs fine, never run lean, webers rarely fart on cold mornings.
jeff taylor has a triple webered nissan 6 motor running at 1 psi too. (2 webers + 1 dellorto)

overall it seems to make the tank last longer now and less messy fuel crap around the webers. (less cleaning)

is what i thought when i was told 1psi..
now i know it works.

Thanks all,
Turns out that either the tank is rusted/clogged or (I'm hoping) that the fuel line has a restriction. I'm currently pumping the petrol out of the tank to where it is low enough for me to open the drain valve and try to flush it out. I also have new metal pipes to make a new petrol line from tank to engine compartment.

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If you are going to the trouble of replacing your fuel line from the tank to the motor, use a bigger line. I'm about to replace mine with 3/8. The stock 1/4 line can't supply enough juice to feed my engine. if you ever want to throw in a nasty engine, you'll need a bigger line to feed it.

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I drained the tank, and there was zero rust or debris. Could have been some water as the fuel looked slightly cloudy, but I think the tank is okay.

With the tank looking better than I expected, I hooked up an air line from the tank side of the fuel line and blew about 80 lbs of air pressure through the line. I could see a little bit of debris come out of the line and there didn't appear to be any rusted bits coming out.

With the tank flushed and the line appearing clear, I installed new rulber lines and a fuel filter, and the datto started right up and has been running fine. I have been driving it around all morning with no problems.

I can make a new line if I have to, but I think blowing it out was all that was needed.

Thanks again for everyone's help. This forum has been a big help keeping my Datsun on the road.