Since being in Australia, try a holden Gemini radiator. I think there were two types fitted, the older gemini radiator is the better choice (plumbing in right areas).

This radiator has the in/out plumbing in the right areas (no need to buy/adjust your hoses), and would need little mounting work to fit, (and has a greater surface area, thus more
cooling effect).

You couldn't pay more than $50 for a good second hand one.

This is an anaesthetic, not a cure for your problems. Standard Datsun cooling should be sufficient for stock A14s. I have a mild cam, high comp/worked head, twin carb A14 which
runs stock cooling (no overheating - so why change it?).

You may also try to put a bigger spacer between the fan and the pump to get the fan closer to the radiator. Try cleaning your heater core in the dash board and alway have it
blowing hot air. That heater core acts like an extra small radiator. Also try looking for contricting (closing) hoses that may block water flow. Laters.....

Hopes this helps...

Sergio

To add to the chin spoiler or airdam idea. Do you have the fan shroud installed? (My old Montero had the same problem untill I replaced the missing fan shroud)Is it a direct
drive fan bolted directly to the W-pump? If so maybe an electric fan conversion might work if you haven't already tried it. Make sure your antifreeze is a 50/50 mix, I'll bet you
don't need the -45deg.C protection, but a mix like that also raises the boiling temp of the coolant, which may help you.
You could also try a higher pressure rad cap. Go from 0.9 bar to 1.1 bar(14psi to 18psi Approx) This will also increase the boiling point of your system.
Good luck.

I think you should just try to get as large of a radiator you can fit. I have a new one from a 76 B210 (manual tranny) and I haven't had any overheating problems. Also, an
electric fan from any car at the junk yard would help.

Your overheating may be caused by lack of air flow though the radiator at higher speeds. Installing a air dam or deflector at bottom
of radiator may help.
Bob

Do you have Nissan Urvans there? - they're worth checking for a
radiator.

oops logged in with wifes id sorry

over 18 months ive had 2 x 1200s 1x1400 3 radiators, all had tanks removed and cleaned, new thermostats, cap, all different distributor settings, my 1200 ute is on gas and has an
acumiltive heat problem from 110kmh onwards, slowly gets hotter untill it overheats, slow down a little and the temp comes down. with large jetting on petrol it still over heats, any
suggestions on a cheap alternative radiator avail from a wrecker??? $300 quoted for a 3 core h/d one tooo dear, no budget, just need to get to work and back, even on a hot day 80kmh is
out of the question??? thanks buzzard, the blown 1530cc sounds interesting??