As opposed to rebuilding a motor without porting the head or touching the bottom end.

Now that's maximum effort for minimal gain...(that's what I'm doing at the mo')

The gain you get other than performance is learning how to do it...man I should have been a school teacher with that sort of attitude..hehe

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That must be a big plus.
I hate the noise the mechanical fan makes when you are giving your engine a bit of boot. It sounds like a airplane infront.

I did think about removing the mechanical fan and installing a electrical fan, but noticed that it will be alot of effort.
I will have to remove my radiator to get proper space to bend open the safety clips on the fan's bolts and to undo the bolts.
That is why I said it is so much effort to do it with minimal gains.

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i ran a mechanical fan on the same motor the elec fan is now on. the only change is i now have a bigger radiator, but it was originally installed on the stock one. can't say i noticed any power difference at all ?? if there was it was extremly minimal ..... biggest change was noise - much less from the electric. i have it wired thru a relay and thermal switch with fuses where they need to be and have never had a problem ?? if it's wired correctly with the right fuses and wire(amp rating) it should be no less reliable than a thermo fan set up on a $100,000 car ??

there are issues with messing with the fan.

I had to bolt my pulley on and cut the extra threaded bits off the studs.

once you have a fan, relay, temp sender, then you need a way to mount it, if you're not using a fan from another car then have fun making a new shroud. why? well if you use those handy mount the fan directly to the radiator things and live somewhere bumpy, your radiator will break, and it won't happen somewhere where it's easy to deal with.

so you got all that, :) my fan pulls over 30A at startup, i've seen it pop 30A fuses instantly. mine is wired more or less directly to the battery through a relay so it only runs when the car is on.

Adding a light is a good idea, as is an always on switch. I don't think an adjustable fan controller is worth using.

if you don't use a relay it will work for a while, but the thermal switches burn up for me because of the fan's power draw.

i have a standard 60A alternator and it works fine, but up to a point more is better.

if you're concerned about the alternator drag, you could rig up a bypass that takes the alt offline, yes you can do it, and it will free up a little bit more power ( about 600W for you KW people ) you can tun the car for an hour - several hours depending on electrical draw like that.

The typical setup I have seen is to wire the fan with an override switch in case the 'stat or thermal switch you're using fails, or just for peace of mind (a 'running' indicator lamp wouldn't hurt either). And contrary to popular notion, the battery is there for one job: Starting. Once the car is running, the alt. is running everything. The idea is the loss from the extra drag imposed by the increased electrical load on the alt. is less that the loss of the mechanical fan. A 'puller' fan is much preferred to a 'pusher' as it dosen't block the airflow, a pusher will cycle more often in the same conditions. A puller will have to be slim to fit in front of the water pump pulley, I will be fitting one I have soon. I will also fit a larger alt, as a fan can draw as much as 10 amps.

the worst part is those annoying times when the thermal switch is not working and the damn thing gets too hot unexpectedly, mech fans just about never cause you to not have any cooling at all.

that said, i watch my temp and have an electric fan.

being able to precool before stomping on it hard is a nice thing for getting on the highway or competition.

i always like the electric fan, i have mine on a manual switch, once your over 40k's no need to be on, plus you can cool your rad with the engine off.

Boofhead

No, I don't think so. I can tell the following:
There is a guy here where I live that drag raced a Datsun coupe with a A15 motor in it. It was obviously worked with 40 sidedraft webers and a 300 cam.
He used the mechanical fan.
They removed the mechanical fan and changed to electrical fan. They blew head gasket due to overheating. I think the fan did'nt work correctly. They then changed back to mechanical fan.

The quarter mile times were'nt affected.
I also think you will see the difference on the dyno.

Boofhead.
Did you run a mechanical fan before changing over to electrical fan?
And when you switched over to electrical, did you notice any difference.
My posts I purely give on theory and not practical experience. So I may be wrong.

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so if it's at night, cold and raining .... wipers are on, lights are on, and heater fan is on then your car will go slower due to the electrical draw on the battery and the alternator trying to keep the charge up ????

The only way to know for sure would be too stick it on the dyno with the mechanical fan on, then take it off, do a second run, then fit the electric fan and do the third run.

I think at peak rpm the electrical fan will start winning...and peak rpms are where the most power are.