Im looking for an electric to cool down my 289. How much CFM should I be looking for? How much CFM does a stock engine driven fan put out?

 

Try these and see what you can find out. My elec fan can drop my temp guage 10* in no time, and I THINK it is a 1800cfm style.

http://www.derale.com/main.shtml

Should help some, I hope.

 

are elec fans really worth it? my mustang is never really gets too hot even in miami stop and go traffic.

 

IMHO, Yes they are. They not only free up the engine from the task, but they cool 10x better.

 

Do I need a new alternator if I add an electric fan?

 

That depends on what other stuff you have pulling on your alternator, such as a fancy stereo system. Read the specs on the new fan to determine what amperage alternator you will need.

 

I hard wired mine in with an in-line fuse. Just ran it off a toggle switch. Make sure you get a big enough fuse(20 amp) to carry the amp/volts or it will blow them. I went with a 15 amp fuse, per the counter guy at the Zone, and it does fry them after awhile.

 

If you don't mind going away from stock, a 100 to 140 Amp alternator would do a really nice job. It would clean a lot of the back feed and spikes we get with our antiquated systems, and give a solid base for adding on electronic components. I've had good luck with the single wire alternators (new, I'm not much into buying rebuilt stuff unless I have to).

Very easy install. You can either cap off and tape the unused wires into the harness, or untape the harness and remove them all together (as long as you don't want to go back to stock).

Car will only draw what it needs, so there is no worry as to having too much.
If you decide to go with electric fan(s) (which I think is a great idea), I'd really consider this upgrade.

One other thing I like is cicuit breakers for electric fans. They are a little more tolerant of the high spike on startup of the fan. The down side is, if it does fail, it's more work than replacing the fuse. Another option is a fuseable link, which is also very tolerant of high start up current.

 

I was wondering about the 1 wire alternators. If i installed one on my 66, and cap off the other wires, will my Amp guage still work?

 

Great question!

The simple answer is no, but one jumper wire will make it work.

On the '66, you can make it work (as good as it ever did) by running a jumper from the harness plug to the Batt terminal of the alt. This jumper goes to the yellow wire that is at the 4 pin connector right below the alternator. Connect it to the engine harness side, The other side gets removed, with the old alternator. So basically you would need a 12-14 gauge wire, an eyelet, and a large male bullit connector.

I would strongly suggest using this oportunity to install a volt meter. The stock amp gauge did a very poor job of telling the driver what is going on with the charging system. In fact, given a choice between an idiot light and the Amp gauge, as it is wired, I'd take the idiot light.