Hey Guys

The last couple of days alot of ppl have been telling my to remove the Mechanical Fan. Does it Really make sutch a Diffrence in the motors Rev'ing, by putting on a Electrical fan ?

Any Clarity on the subject would be appreciated.

it keeps the engine better cooled at low speeds and frees up a little power.

is worth $100? not unless you have money to throw around.

Mr Datsun is a very clever bloke and I'm sure that if he thought it was worth the effort of putting an electric fan on then he would. Cheep fan = more horspower/better cooling = more sales.
Olboy

Quote:

Now are you saying oldboy that Datsun as an automotive company would have put the thermo on if they thought it was good? And the reason they have a mechanical fan is because it is better?

I think it would be fair to say that the mech fan is cheaper and that's why its fitted to the A series engines.

But better, that is rarely why an automotive company picks a component or method.

If you look at any make of car from the early '70's, very few if any had electric fans. They were expensive & unreliable compared to today's sytems. A vast majority of cars on the road were, front engine- rear drive, like the 1200. It was dead cheap & easy to bolt the fan on the water pump & away we go.The next step was to mount the fan on a temperature sensitive hyfraulic clutch that was then bolted on to the water pump. Hot rad, hot airflow, clutch engaged, fan driven Cold rad cold airflow, clutch/fan freewheeled, less drag more power & economy. (Clutch fans are still very common on light & heavy trucks because of their durabilty.) The next setup is what we see on cars today. An electric fan is almost the only way to go on a front wheel drive car. The engine is sideways most of the time, so the water pump is pointing the wrong way to mount a fan. The new fans are very efficient, & when thermostatically controlled only run when needed.
When my mom's '73 1200 sedan was new my dad used to take the fan off completely for winter driving, which gave better performance & fuel mileage. (You must realise we live in Canada, where it's on the cold side in winter).I wouldn't recommend doing this to anyone now however. I think an electric fan conversion would be worth while if done properly. I'm sure many members on this site have already done so. I would think that the auto wreckers would be a good source for a cheap fan. A Honda Civic, or Nissan Sentra rad fan might work well. One can only guess, but I would immagine that a several HP increase would found, especially at higher RPM's.

This is what I figured out through theory.
Anyone welcome to confince me otherwise.

When driving in slow town traffic, the mechanical fan will work due to low airflow from the front. BUT. As soon as you start to pick up speed and wind starts to come from the front, I think the airflow will eventually start to match the airflow at the back of the mechanical fan.
Meaning, wind coming from the front will start to cancel out the suction created by the mechanical fan.
For drag racing, you will score little bit of power. Maybe 5hp.But for racing purposes I think you will waste your time and money because you will have constant high speed airflow canceling out the mechanical fan.
Anyone else
Not worth the time, money and effort.

You will maybe reduce the noise from the engine compartment.
I have noticed under high revs that these mechanical fans can make alot of noise.

mmh.

That is also what i have been told DaveB, The ppl building performace A series engine's say the mechanical fan renders useless after bout 60 km/h , but then again i makes one wonder if the A class engine's Durability doesn't stick with the fact that it is always "cold" or cooled. Does anyone have proof of this ?

termo/electric fans are good, they are quiter than the mechanical fan, will cool better while the cars sitting in traffic or at slower speed, they will free up minimal power to the engine. It can be done cheap with the most expensinve item of the upgrade is a thermal switch (if you go new) these are around $55 aus dollars for a davies craig one. the fan bought second hand can vary from $10 aus dollars to what ever you're willing to spend ??
this is what i did with my sedan



this is a n13 pulsar fan installed in the front as a blow thru set up - blades are reversed as to is the polarity of the motor by swapping the wires to the opposite terminals.

I have the same elec. fan on mine & have had no problems at all . cheap & easy to find in any wrecking yard.

yes, there is a speed where the airflow is almost the same as having the fan going, but even at 120 kph the fan may still kick on to suck more air through. i had one that i could leave on all the time or let the thermostat control and even at high speed it ran cooler with the fan in on all the time mode.

that speed also increases as the temp and humidity go up. there will be a point where the airflow just doesn't do it.