I currently have a newly rebuilt 3 core radiator(stock casing) and a flex fan in my 67 mustang. 302 engine. I can run my car for about an hour in the spring and probably 20 min in the summer before it overheats. I would like to change out the flex fan and install a electric fan. I have just over 5 inches of space between my belts and rad when I take out the flex fan. Is this the best way to get more cooling? If so has anyone used a fan/should that works well? Be nice if the fan, Shroud, temp sensor to turn it on was all a package. Also i have the stock alternator on the car, I'm thinking I will have to replace it wit ha 100 amp alternator.
Whats everyone's thoughts??

 

does it overheat only at speeds under 30mph?
Does it overheat at speeds above 30...ever?

 

The car is mainly a Sunday driver. I haven't taken it out of town yet. So to answer your question it overheats under 30. Not sure over 30

 

Well what indications do you have that it is indeed overheating.

Lets say the stock temp gauge is giving you bad data... could you still be sure it was overheating?

 

The gauge is old but seems accurate. I have a heat gun that I use on the block. It's defiantly
overheating

 

what did the temp gun say?

To answer your question yes the felx fans sux
yes I like electric fans and I have tired a couple. I have the derale now I like it but the temp probe they use does not work well and requires mods. A more reliable system is the Flexalite Black Magic direct fit fan with shroud (complete package). This fan I ran daily driver for about 10 years and it was very reliable (as good as the wiring job you do (solder everything)) The temp probe was very accurate and well tuned to the system and accurately measured temp from the radiator fins. The motor is good quality and so are the start relays. I would recommend this system it draws about 15 amps and kept my 300hp 302 within spec in 105deg heat using an aluminum radiator from Norther.

Another option is clutch fans which I have never used but some dudes really like them too.

 

I used a 4 core brass oem radiator w/ a factory shroud and a factory flex fan out of a 77LTD with a tow package and I could let that car idle around in traffic all day long on a 100º day and never get above 195. I used both the factory dash gauge and a Stewart Warner under dash temp gauge to keep an eye on things. fwiw, I also did that with my oil pressure gauges.

 

Thanks for the info!!!! I was looking on the Flexalite website, typed in my car and the fan that was recommended was only 1250 CFM. Do you think this is enough?

 

not sure..maybe talk to a tech I dont remember how much mine pulled but I think it was close to that